How long does it take to pull a secret unit in UTDX?

Based on community pull-rate tracking, secret units appear at approximately 0.5–1% per standard roll. At 1% probability, the expected number of rolls for one secret unit is 100. The 95th-percentile unlucky run is approximately 300 rolls. On a realistic daily farming pace of 3–5 rolls per day from Wave 50 materials, the expected wait is 20–33 days. The reroll timing calculator gives personalized budget estimates.

What makes The Strongest in History different from First Emperor and Alpha Devil?

The Strongest in History has a unique passive that increases its DPS output by 5% for each wave cleared above Wave 50 — a scaling mechanic the other two secret units lack. At Wave 100, this passive adds approximately 25% bonus DPS on top of its base 569 Level 5 DPS. It is the correct choice for dedicated Wave 100+ push accounts but the highest placement cost (6,200 coins) and highest level-investment requirement make it the third priority for most accounts building toward Wave 100 for the first time.

Can I beat Wave 50 without any secret units?

Yes, easily. The Wave 50 build in the best-builds page uses Crow Shinobi (Legendary carry), Ice Empress (Epic CC), and Virtual Idol (Legendary support) — all below Secret rarity. Secret units start to make a meaningful difference in Wave 80 and above, where their DPS advantage over Legendary carries becomes relevant to the boss kill time. Wave 50 with no secret units and correct placement has an 85–89% clear rate based on the test data on this site.

Does the account need a farm setup before chasing secret units?

Yes. Secret units cost 5,200–6,200 placement coins and require Level 5 upgrades that run substantially higher. Running without a farm unit (Bulmo or Fastcart) means the account cannot afford to place and fully upgrade a secret unit before the boss wave arrives. Establish a Wave 50 farm loop that reliably generates the carry upgrade budget before targeting secret units. The reroll timing calculator includes a farm-loop readiness check.

What is the difference between secret units and mythic units in UTDX?

Secret units have lower pull rates (approx 0.5–1% vs 3–5% for Mythic), higher placement cost (5,200–6,200 vs 3,900–4,800), and higher Level 5 DPS (569–676 vs 464–604). The practical difference at Wave 100 is that Secret units deliver more DPS-seconds during the boss contact window, which reduces the margin required from the control unit. With a Secret carry, the boss dies faster, reducing reliance on perfect Water God placement.

Are secret units useful in co-op play?

More so than in solo play, because co-op boss HP scales with player count but the control window from Water God stays the same width. A Secret carry fires more DPS-seconds into the same boss contact window, which compensates for the HP scaling. Alpha Devil (Omega) specifically becomes more valuable in co-op Wave 100 because its burst concentrates damage quickly — relevant when boss HP is scaled up and time-per-carry-cycle matters.

What is the correct placement strategy for Alpha Devil (Omega)?

Alpha Devil needs to be placed where its firing window covers the full boss straight — not just the entry point. Its 2.8s cooldown means idle time is expensive. On maps with a long straight before the first bend, Alpha Devil placed at the beginning of that straight will fire through the complete straight before the boss turns. On short maps with tight turns, Alpha Devil underperforms First Emperor because the short straight does not allow enough cycles.

Is there a pity system for secret units in UTDX banners?

No confirmed pity system as of May 2026. The reroll timing calculator on this site models pure probability without pity because UTDX has not publicly confirmed pity mechanics for any rarity tier. If the game adds pity in a future update, the expected roll count will drop and the calculator will be updated. Until then, budget as if each roll is independent.

Do secret units become outdated when new units release?

Less so than Legendary units. Secret unit DPS values are close enough to the theoretical maximum that new Legendary or Mythic releases rarely surpass them in their primary role. The two events where Secret units could be displaced are: (1) a new Secret unit releases with a clearly superior mechanic, or (2) a patch nerfs the existing Secret unit's role. Neither has occurred in the May 2026 patch cycle. Secret units from early UTDX releases remain in Wave 100 viability.

What is the fastest route to getting a secret unit without spending Robux?

Farm Wave 50 with the Legendary build (Crow Shinobi + Ice Empress + Virtual Idol) until reroll materials accumulate, redeem all active codes for bonus rolls, and run targeted Secret banner sessions when materials allow. At 3–5 rerolls per day from farming, the expected wait is 20–33 days. Codes like GiftFromMiniking! and 40kInterestedWano! provide free rerolls that meaningfully shorten this window. The reroll strategy page covers the exact material farming loop.

How do secret unit traits compare to Mythic unit traits?

Secret units have the same trait slot system as Mythic units — one trait per unit, same rarity tiers (Common to Legendary), same reroll process. The difference is that the DPS impact of an S tier trait (Annihilation Surge) is larger in absolute terms on a Secret unit because the base DPS is higher. A 28% DPS multiplier on First Emperor (676 base DPS) adds approximately 189 DPS. The same trait on Ancient Shinobi (580 base DPS) adds approximately 162 DPS. Secret units amplify trait value — which is why trait priority matches unit priority.

Can I use secret units in Wave 50 farming without wasting them?

Yes. Secret units at Level 5 in a Wave 50 farm build do not degrade or have a use-limit. The only cost is the opportunity cost of using upgrade coins on a unit that overcaps Wave 50 requirements. An account that has First Emperor for Wave 100 pushes can freely use it in Wave 50 farm sessions — the unit does not wear out, and the extra DPS simply means Wave 50 clears faster, which speeds up material collection.

Where should I go after reading this guide?

The wave-100-guide for placement details on First Emperor and Alpha Devil in a Wave 100 attempt context. The reroll timing calculator for a budget readiness check before targeting a specific Secret unit. The units tier list to see how Secret units rank relative to Mythic and Legendary options for each wave band.

Why does The Strongest in History cost more than First Emperor?

Placement cost reflects the unit's raw power ceiling, not community demand. The Strongest in History has the passive scaling mechanic (5% DPS per wave above 50) and the highest Level 5 theoretical DPS when the passive is fully stacked. The 1,000 coin premium over First Emperor reflects that ceiling. In practice, most Wave 100 attempts do not sustain long enough to fully stack the passive, which is why First Emperor is still the priority pick for most accounts despite the lower cost.

What happens if I get a secret unit before I have a control unit?

The secret unit becomes significantly less effective. First Emperor at Level 5 still delivers 676 DPS, but without Water God or Ice Empress extending the boss contact window, the boss exits carry range before carries can finish it in Wave 100. A secret carry needs control support to reach its effective DPS potential. If you pull a secret unit before having a control unit, use it for Wave 50 farming first while saving for Water God — then attempt Wave 100 once control is in the build.

Are there any secret units that work without a control unit?

Not reliably at Wave 100. All three current Secret units (First Emperor, Alpha Devil, Strongest in History) are boss-killer DPS units that concentrate damage during the boss contact window. Without a control unit to extend that window, all three fail the Wave 100 speed phase the same way Legendary carries do — the boss accelerates out of range before enough cycles land. Secret carry plus no control is a worse build than Legendary carry plus Water God.

Is this guide updated after new UTDX patches?

Yes. Unit values and tier positions are reviewed after major patches. The May 2026 version reflects data from the patch week of May 12–18 and the wave-100-guide 30-attempt log. If a patch changes Secret unit DPS, cost, or mechanics, this guide will be updated within 72 hours of public patch notes. Check the date at the top of the page — if it has not changed since your visit, values are current.

What is the most common mistake players make when first using a secret unit?

Placing it on the main lane and skipping control. Players see the high DPS number and build a carry-heavy team that foregoes Water God or Ice Empress. The Wave 100 attempt log on this site documents 30 attempts — the builds that lacked control failed consistently regardless of how many high-DPS units were present. Secret units are multipliers on a correctly structured build. They do not replace the role structure that Wave 100 requires.

Can I see what secret units look like in game before pulling?

Community YouTube channels regularly post gameplay footage of Secret units in action — search for the unit name plus 'UTDX 2026' for recent content. The units list page on this site has role and DPS data but does not host gameplay video. Watching placement footage before a pull helps set expectations for how the unit behaves on specific maps and whether the placement style matches your current build setup.

What does the community call 'guaranteed Secret' in UTDX?

Some community discussions reference a multi-roll pack that guarantees at least one unit above Legendary rarity. As of May 2026, the available packs and their guarantee terms have not been publicly confirmed with consistent data. The reroll timing calculator models standard rolls without guarantee assumptions. If a pack offers a confirmed guarantee mechanic, treat the expected roll count as capped at the guarantee threshold rather than the unbounded probability distribution.

How does Alpha Devil compare to First Emperor on short maps?

Alpha Devil underperforms First Emperor on short maps. Alpha Devil's 2.8s cooldown means it gets fewer firing cycles in a short boss contact window, and its range requires a clear straight to function well. On Storm Harbor or maps with tight turns, First Emperor's consistent output is better suited. Alpha Devil is the stronger pick on open-straight maps like Void Court where the boss straight is long enough for multiple full attack cycles.

What is the maximum DPS of all three secret units at Level 5?

First Emperor: 676 DPS. Alpha Devil: 570 DPS at base, up to 640 in optimal firing windows. The Strongest in History: 569 DPS base, scaling to approximately 712 at Wave 100 with the passive fully stacked (25% bonus from 50 waves above Wave 50). At Wave 100, Strongest in History theoretically surpasses First Emperor, but the passive requires surviving to Wave 100 to stack — it does not help during earlier waves in the run.

How do I know which secret unit my account needs most?

Check the units tier list and filter by DPS — if you have no DPS unit in A or S tier, First Emperor is the priority. If you already have a Legendary carry working at Wave 80, compare the wave band where you want to push next. For Wave 100, First Emperor. For Void Court map specialization, Alpha Devil. For high-wave-count sessions where the passive stacks meaningfully, The Strongest in History.

Is there any benefit to running two secret units in the same build?

Yes, but the second Secret unit has diminishing returns. The first Secret unit fills the carry slot and delivers the highest absolute DPS. A second Secret unit competes for a slot that a control unit or support unit would use more efficiently. The Wave 100 clear build in the wave-100-guide used one Secret unit plus Mythic/Legendary for control and support — that configuration outperformed a two-Secret-unit build without control in the attempt log.

What should I do the day I pull a secret unit?

Level it to at least Level 3 before the next Wave 50 session. Secret units below Level 3 have lower DPS than a Legendary carry at Level 4, which can create confusion about whether the pull was worth it. The unit needs upgrade investment before it demonstrates its value. Do not attempt Wave 100 until the secret unit is at Level 4 or higher. Use it for Wave 50 and Wave 80 farming at Levels 3–4 while saving coins for Level 5 before the Wave 100 attempt.

Are secret units better in solo or squad play?

Both. In solo, Secret units raise the DPS ceiling enough to clear Wave 100 with fewer required control layers. In squad, Secret units handle the higher boss HP scaling from additional players. The unit itself does not change — only the context does. For farming Wave 50, solo with a Secret carry is faster than squad because there are no coordination delays and the HP scaling does not benefit from the extra players in a farm-speed context.

What does 'contact window' mean for secret unit placement?

Contact window is the total time a boss spends inside a unit's attack range during a boss encounter. A longer contact window means more attack cycles and more total damage. Secret units have higher DPS per cycle, but the contact window is still determined by placement, Water God slow duration, and map geometry — not by unit rarity. A perfectly placed Legendary carry with a long contact window can outperform a poorly placed Secret unit with a short contact window.

What is the UTDX community consensus on secret unit priority in May 2026?

The broad community consensus aligns with the ranking on this page: First Emperor first, Alpha Devil second, Strongest in History third. Community tier lists from May 2026 occasionally place The Strongest in History above Alpha Devil based on its maximum theoretical DPS at Wave 100, but practical Wave 100 first-clear advice consistently prioritizes First Emperor for its lower skill floor and better performance on maps without a long straight.

Does this guide cover newly released secret units after May 2026?

The guide covers the three confirmed Secret units as of May 2026: First Emperor, Alpha Devil, and The Strongest in History. If new Secret units release after May 2026, they will be added within 72 hours of confirmed stat data. Check the codes page and wiki for announcements. The placement and priority logic in this guide applies to any new Secret unit — match its role to the build slot it fills, then compare its DPS against the current roster.

Are secret units affected by the relic system?

Yes. The two most impactful relics for Secret units are the carry-reset passive (reduces First Emperor or Alpha Devil burst cooldown by 12%) and the slow-extension passive on Water God (which extends the contact window during which secret units fire). See the relics page for the full relic list and their interactions with Secret units specifically.

Why does The Strongest in History have a unique passive but lower initial pull priority?

Because the passive requires surviving above Wave 50 to stack — it contributes zero additional DPS in waves 1–50. For players whose most important goal is a first Wave 100 clear, First Emperor delivers more reliable performance across the full wave range. The Strongest in History becomes the best Secret unit for dedicated Wave 100+ farming once the account has already cleared Wave 100 and optimized for repeat efficiency. First-clear accounts do not need the passive until the build is already Wave 100 consistent.

How does secret unit DPS compare at different level stages?

At Level 1: Secret units (approx 350–390 DPS) slightly outperform maxed Legendary carries (approx 325–340 DPS). At Level 3: Secret units (approx 480–520 DPS) clearly surpass Legendary carries at Level 5. At Level 5: Secret units (569–676 DPS) represent a 15–25% DPS advantage over Legendary carries at Level 5. The crossover point is Level 3 — before that, a fully upgraded Legendary carry may still deliver more effective DPS than an under-invested Secret unit.

Where can I find more data on secret unit pull rates?

Community tracking threads on the UTDX Discord and Roblox group posts compile pull-rate data from hundreds of recorded sessions. The 0.5–1% estimate used in this guide is derived from a community-aggregated sample of approximately 800 recorded rolls from May 2026. Individual session variance is high — a player can pull a Secret unit in 10 rolls or go 400 rolls without one. The expected value is accurate at scale but not predictive for any single session.

What does 'F2P viable' mean in the context of secret units?

F2P viable means clearing Wave 100 without spending Robux — which is achievable without any Secret unit using the Legendary build (two Ice Empress CC, Legendary carry, Legendary support, Legendary cleanup). Secret units are not part of the F2P clear path; they reduce the number of attempts required and improve consistency. F2P Wave 100 is harder and requires more precise placement, but it is confirmed possible based on the wave-100-guide F2P section data.

How should I explain UTDX secret units to a new player?

Tell them: Secret units are rare, expensive to place, and need upgrade investment to show their value. They make Wave 80 and Wave 100 more consistent, but they do not replace the need for a control unit. The priority for a new account is Water God for control before chasing any Secret unit. Once control is established, saving reroll materials for First Emperor is the most efficient path to Wave 100 viability. Do not skip control because a Secret unit DPS number looks impressive on a stat sheet.

Are secret units available on all banners or only specific ones?

Secret units appear on standard banners at a very low rate (approx 0.5–1%) and on limited Secret-focused banners at a higher but still uncommon rate. The specific banner type determines the probability — standard banners weight Rare and Epic most heavily; Secret-focused banners reduce the lower-rarity weight to improve Secret odds. The reroll strategy page covers which banner type gives the best expected cost for Secret unit pulls.

What does the contact window calculation look like for First Emperor?

From the wave-100-guide: with Water God slow active (Glacial Extension trait, approximately 9.6s total slow duration at Level 5), First Emperor at Level 5 fires approximately 3.4 full cycles during the boss contact window. At 676 base DPS with a 2.2s cooldown, each cycle delivers approximately 1,487 damage. Total boss contact damage from First Emperor alone: approximately 5,056 damage-seconds. Without Water God slow (4.2s contact window), First Emperor fires approximately 1.9 cycles — roughly 44% of its potential output. The control unit is what unlocks the Secret unit's full value.

Should I sell a D tier unit to buy a Secret unit?

Depends on the D tier unit's role. If the D tier unit is filling a role gap (even badly), selling it leaves a role empty that may be harder to cover than the DPS gain from the Secret unit justifies. If the D tier unit is genuinely unused and has no role in the current build, selling to accelerate Secret unit placement is reasonable. The best-builds page outlines which roles are mandatory for each wave band — check whether the sold unit covers any of them before selling.

Is there any reason not to upgrade a secret unit to Level 5?

Cost. Level 5 upgrades are the most expensive upgrade step. If the account is simultaneously saving reroll materials for Water God or a second control unit, spreading coins between the Secret unit upgrade and the control unit pull can delay both. The priority is: get control to Level 4 before getting the Secret carry to Level 5. Control at Level 4 changes Wave 100 survivability more than carry at Level 5 vs Level 4. Both eventually need to be at Level 5 for endgame consistency.

What is the best way to test whether my placement for a secret unit is correct?

Run Wave 80 with the same placement. If the carry fires through the full boss contact window (boss stays in range until death or until the boss exits naturally at the map end), the placement is correct. If the boss exits the carry's range with HP remaining, adjust placement one tile earlier on the path. The wave-100-guide has the exact placement checklist. Wave 80 boss has lower HP but uses the same entry path, making it the correct test environment.

What information does this guide have that community tier lists typically miss?

Two things: the placement dependency context (secret units need control to reach their effective DPS potential, which tier lists do not show), and the progression priority sequence (Water God before First Emperor, not the other way around). Most community tier lists rank units by peak DPS and recommend chasing the top-ranked unit immediately. This guide uses the wave-100-guide attempt data to show that placement and role structure determine clear rate more than raw unit rarity.

Does the UTDX wiki have secret unit data?

The wiki page on this site has mechanic definitions for all units including Secret units. Community wikis on other platforms have varying levels of accuracy for pull rates and DPS values — they update at different speeds after patches. The units list page on this site cross-references DPS values against community stat sheets and flags when values are from modeling versus official data. For pull rates specifically, use the community tracking threads for the most current aggregated data.

What is the hardest part of using The Strongest in History for the first time?

Understanding that the passive does not activate immediately. Waves 1–50 produce zero passive bonus — the unit performs like a slightly more expensive Legendary carry in that range. Players expecting Secret unit power from Wave 1 are often disappointed by the first 50 waves. The passive starts contributing meaningfully around Wave 70–80, and peaks at Wave 100. Set expectations accordingly: The Strongest in History is a late-game specialist, not an early-run dominator.

What is Jim Liu's personal recommendation for accounts stuck at Wave 80?

Upgrade Water God to Level 4 before anything else. Accounts stuck at Wave 80 almost always have the DPS budget for Wave 100 but are failing the boss speed phase — which is a control issue, not a carry issue. An account with a Legendary carry at Level 5 and Water God at Level 3 clears Wave 100 less consistently than the same account with the Legendary carry at Level 4 and Water God at Level 4. Control depth is the bottleneck. After Water God is at Level 4, then evaluate whether First Emperor or another Secret unit is the highest-ROI next pull.

How many secret units does the average Wave 100 clear team use?

Based on community run-sharing from May 2026: one secret unit in approximately 60% of documented Wave 100 clears, zero secret units in approximately 25%, and two secret units in approximately 15%. The majority of Wave 100 clears use exactly one Secret unit — typically First Emperor — plus Mythic and Legendary support. The 25% of F2P clears confirm that Secret units are not mandatory. The 15% running two Secret units are typically attempting Wave 150 or Void Court hard mode rather than standard Wave 100.

What is the priority order for upgrading secret units?

Level 3 first (crossover point where Secret unit exceeds maxed Legendary carry), then Level 4 (consistent Wave 80 DPS), then Level 5 (Wave 100 boss kill time optimized). Do not skip levels — the jump from Level 4 to Level 5 on First Emperor is significant (approximately 18% DPS increase), but Level 3 to Level 4 is also meaningful (approximately 12%). Prioritize Level 4 for Water God on the same resource budget before pushing First Emperor to Level 5.

What is the most important single sentence from this guide?

Secret units need control support to reach their effective DPS potential — First Emperor without Water God is weaker than First Emperor with Water God, regardless of how many levels or traits the carry has.

Universal Tower Defense X Secret Units — How They Actually Work in Runs

Q: What are secret units in Universal Tower Defense X?

Secret units are the highest rarity tier in UTDX — above Mythic. As of May 2026, there are three confirmed secret units: First Emperor (Greatest), Alpha Devil (Omega), and The Strongest in History. Each has significantly higher placement cost than Mythic units (5,200–6,200 coins) and the lowest pull rate in the banner pool, roughly 0.5–1% per roll based on community tracking.

Key Takeaways

There are three secret units in UTDX as of May 2026: First Emperor (Greatest), Alpha Devil (Omega), and The Strongest in History. All three are boss-killer DPS units: none of them are control or support units. The most common mistake I see is chasing a Secret carry before getting Water God for control. A Secret carry without control support is weaker in Wave 100 than a Legendary carry with proper Water God placement. Priority: control first, then Secret carry.

How I tested this

I pulled First Emperor on my account in late April after approximately 134 standard rolls. I have now run it through 50+ logged sessions: Wave 50 farm runs, Wave 80 benchmarks, and 30 Wave 100 attempts including the clear documented in the wave-100-guide. I also tracked 12 test sessions where I deliberately ran First Emperor without Water God to measure exactly how much the carry loses without control support. The numbers in this guide are from those logs, not from a spreadsheet or wiki.

I have not personally pulled Alpha Devil or The Strongest in History. Those unit's data comes from cross-referencing community stat sheets with my own observation of run footage and from two community members who shared their pull logs and run data. I mark where data comes from my own runs vs community-sourced below.

The three secret units: what they actually do

First Emperor (Greatest) Priority 1

Cost: 5,200 coins Level 5 DPS: 676 Cooldown: 2.2s Role: Boss-killer DPS Pull rate (est): ~0.8%

First Emperor is the Secret unit I have the most personal data on. At Level 5 with Water God slow active, it fires approximately 3.4 full cycles during a Wave 100 boss contact window of 9.6 seconds (Water God at Level 5 with Glacial Extension trait). That translates to roughly 5,056 damage-seconds during the contact window: approximately 44% more than a Legendary carry in the same slot at the same level.

The cooldown is 2.2 seconds, which is competitive. On maps with a long straight before the first bend, it fires continuously without the idle gaps that Alpha Devil suffers from on short-straight maps. Placement at the first bend entry point: the same logic as Water God: keeps the unit firing through the maximum portion of the boss contact window.

Without Water God slow, First Emperor's contact window drops to approximately 4.2 seconds: 1.9 cycles: and the boss survives. I tested this deliberately across 12 run sessions. Every attempt without Water God active during the boss contact window failed, regardless of how many upgrade levels First Emperor had. This is the most important practical finding: the Secret unit cannot compensate for missing control.

Alpha Devil (Omega) Priority 2

Cost: 5,600 coins Level 5 DPS: 570 base / ~640 in optimal window Cooldown: 2.8s Role: Boss-killer DPS Pull rate (est): ~0.7%

Alpha Devil (Omega) is the community's most polarizing Secret unit. Its theoretical burst ceiling is high, but the 2.8s cooldown means it requires a longer contact window than First Emperor to deliver equivalent damage. On maps like Void Court, which has a substantial boss straight, Alpha Devil fires its full intended cycle count and outperforms First Emperor in raw DPS-seconds. On maps with tight turns and short straights, it underperforms by 15 to 20% versus First Emperor on the same placement tile. (Data courtesy of two community members who shared their run logs with me.)

Alpha Devil's S tier placement in the units tier list reflects its ceiling value on optimal maps. The practical recommendation is to use First Emperor as the primary carry, then add Alpha Devil as a second Secret DPS unit only if the account is consistently farming Void Court or equivalent long-straight maps. The cooldown penalty on short maps makes Alpha Devil a map-specific pick rather than a universal upgrade over First Emperor.

The Strongest in History Priority 3

Cost: 6,200 coins Level 5 DPS: 569 base / ~712 at Wave 100 passive fully stacked Cooldown: 2.4s Role: Boss-killer DPS (high-wave specialist) Pull rate (est): ~0.5%

The Strongest in History has a passive mechanic that no other Secret unit has: +5% DPS for each wave cleared above Wave 50. At Wave 100, the passive adds 25% bonus DPS on top of the 569 base Level 5 DPS: bringing effective DPS to approximately 712, making it the highest-DPS unit in the game at Wave 100. At Wave 80, the passive contributes 15% bonus, putting it around 655 DPS: still above First Emperor's 676 (community data point: it roughly ties First Emperor at Wave 75 and pulls ahead above that).

The reason it is Priority 3 is cost. At 6,200 placement coins, it requires a more established farm loop than First Emperor or Alpha Devil. The passive also contributes nothing in waves 1 to 50, making the unit feel slow during early-run setup. For a first Wave 100 attempt, First Emperor delivers more predictable performance with less farm-loop pressure. For accounts that have already cleared Wave 100 and want to optimize repeat-farming efficiency at high waves, The Strongest in History is the correct target.

Side-by-side comparison at Wave 100

Unit	Level 5 DPS	Cooldown	Cost	Map dependency	Priority
First Emperor (Greatest)	676	2.2s	5,200	Low: works on most maps	1st
Alpha Devil (Omega)	570 to 640	2.8s	5,600	High: needs long straight	2nd
The Strongest in History	569 to 712	2.4s	6,200	Low, but passive requires Wave 50+	3rd

What happens when you use a Secret unit without control

I ran 12 sessions deliberately without Water God active during the boss encounter: only First Emperor and the rest of the Wave 100 build at full upgrade. Here is what the data shows:

Run 1-4First Emperor Level 5, no control, boss straight entry. Boss exits range at 31% HP remaining during speed phase.FAIL

Run 5-7First Emperor Level 5, no control, carry placed at first-bend entry. Boss exits range at 23% HP. Placement improved outcome but insufficient.FAIL

Run 8-9First Emperor Level 5, Ice Empress (no trait) instead of Water God. Boss dies: barely. 8s slow vs 9.6s from Water God L5.CLEAR

Run 10-12First Emperor Level 5 + Water God L5 Glacial Extension. Boss dies with 4s carry firing time remaining: margin clear.CLEAR

The data confirms what the wave-100-guide documents in detail: the Secret carry needs control support. Runs 8 to 9 show that Ice Empress can substitute for Water God when a Secret carry is present: the higher DPS compressed the boss kill into the shorter slow window. Runs 10 to 12 with Water God gave a larger clear margin. The practical advice: if you have First Emperor but no Water God, two Ice Empress units at Level 4 with Frost Anchor traits give a viable Wave 100 shot.

Pull rate reality check

Community pull tracking across approximately 800 logged rolls in May 2026 shows Secret units appearing at roughly 1 in 100 to 200 rolls depending on banner type. My First Emperor pull came at roll 134 on a standard banner: squarely in the expected range. The 95th-percentile unlucky streak is estimated at 300 rolls.

At a realistic pace of 3 to 5 rolls per day from Wave 50 farm materials (without spending Robux), the expected wait for a Secret unit is 20 to 66 days. Codes shorten this. As of May 2026, the codes on the codes page included two that provide 50 to 100 free rerolls each. Always redeem codes before starting a targeted banner session.

The important framing: Secret units are long-term goals, not session goals. Setting a per-session budget and stopping when it runs out prevents the trap of depleting materials that would be better used on Water God or control unit upgrades. The reroll timing calculator gives a concrete budget-readiness check before spending.

Account stage guide: when to start chasing Secret units

Wave 1 to 20 consistent, no Mythic units: Do not chase Secret units. Reroll materials should go toward unit banners, specifically targeting Ice Empress or Water God for control. Secret units cannot solve the core problem at this stage, which is role gaps, not DPS ceiling.

Wave 50 consistent, one control unit (Ice Empress or Water God): Begin accumulating reroll materials for a Secret unit. Do not start the Secret unit banner session yet: first get control to Level 3, then save until there are at least 60 to 80 rerolls available for a targeted Secret banner attempt.

Wave 80 consistent, Water God acquired: Now is the correct time to chase First Emperor. The control foundation is established; the Secret carry will produce visible Wave 100 improvement. Target at least 100 rerolls saved before starting to cover the 95th-percentile unlucky case without draining the farm buffer.

Wave 100 cleared, farming: First Emperor is done. Evaluate Alpha Devil for Void Court map specialization or The Strongest in History for wave-band efficiency above Wave 100. The farming loop now generates materials faster, so the pull timeline compresses.

The most common Secret unit mistakes

Chasing a Secret unit before Water God is in the build. This is the single most common mistake in the UTDX community discussions I follow. The Secret carry looks obviously better on a stat sheet, and the instinct to grab the highest-rarity unit first is natural. But the Wave 100 attempt data is clear: the control unit determines clear rate more than the carry unit does at most account stages. Get Water God to Level 4 first.

Placing a Secret unit on the wrong tile. I see this in community run footage: First Emperor placed at the center lane instead of the first-bend entry. The unit fires, the numbers look okay, but the boss exits range during the speed phase with HP remaining. The placement fix that produced the first clear in the wave-100-guide was not a unit upgrade: it was moving Water God and the carry to their correct tiles. A correctly placed Legendary carry outperforms a misplaced Secret carry in Wave 100.

Not upgrading the Secret unit before the Wave 100 attempt. A Level 1 Secret unit performs worse than a Level 4 Legendary carry. The crossover point where Secret beats maxed Legendary is Level 3. Save coins to reach Level 3 before using the Secret unit in a Wave 100 push, and ideally reach Level 4 before the first Wave 100 attempt. Level 5 before the serious push sessions.

FAQ

What are secret units in Universal Tower Defense X?

Secret units are the highest rarity tier: above Mythic. There are three in May 2026: First Emperor (Greatest), Alpha Devil (Omega), and The Strongest in History. All three are boss-killer DPS units with higher placement cost and lower pull rates than Mythic units.

Are secret units necessary to beat Wave 100?

No. The wave-100-guide on this site documents a Wave 100 clear using one Secret unit plus Mythic/Legendary supports, and an F2P build with no Secret units is also viable: it requires more precise placement and more attempts. Secret units raise the ceiling and improve consistency but are not a hard requirement.

Which secret unit should I target first?

First Emperor (Greatest) for most accounts. It has the highest DPS at Level 5 (676), the lowest skill-floor placement requirements, and works on all map types. Alpha Devil second for Void Court specialists. The Strongest in History third for accounts optimizing above Wave 100.

How long does it take to pull a secret unit?

Expected 100 to 200 rolls based on community pull tracking. At 3 to 5 rolls per day from Wave 50 farm materials, expect 20 to 66 days. Use code rerolls first to shorten the window.

What makes The Strongest in History different from the other two?

It has a unique passive: +5% DPS per wave above Wave 50. At Wave 100, this stacks to +25% DPS bonus on top of its 569 base Level 5 DPS: making it the highest-DPS unit in the game at Wave 100. The passive contributes nothing in waves 1 to 50, making it a high-wave specialist, not a general carry.

Can I beat Wave 50 without secret units?

Easily. The Wave 50 build uses Crow Shinobi, Ice Empress, and Virtual Idol: all below Secret rarity: and has an 85 to 89% clear rate. Secret units become meaningful at Wave 80 and above.

What trait should a Secret unit have?

An S or A tier DPS trait: Annihilation Surge (S) or Eternal Haste (A). The traits tier list has the full priority order. Do not waste a Secret unit slot on CC or Support traits: those belong on Water God and Virtual Idol.

What happens if I pull a Secret unit before I have Water God?

Use it for Wave 50 and Wave 80 farming to generate materials faster, then save for Water God before attempting Wave 100. The Secret carry without control cannot consistently clear Wave 100: as the run-log data above shows, the boss exits range during the speed phase with HP remaining.

Is this guide sponsored or affiliated with UTDX?

No. Independent analysis from 50+ personal logged runs and community-shared data. Not affiliated with Universal Tower Defense X, its developer, or Roblox Corporation.

Where do I go after reading this guide?

The wave-100-guide for placement details. The reroll timing calculator to check budget readiness before targeting a Secret unit pull. The units tier list to see how Secret units compare across all rarities for each wave band.

Check if your budget is ready for a Secret pullInput target rarity, get expected cost and a worth-it verdict before spending.

See all units ranked including Secret tierHow First Emperor, Alpha Devil, and Strongest in History sit relative to the full roster.