Build it. Multiple 2026 tier lists put the Laetum at or near the top of the secondary category, and the Incarnon mode backs up the hype with real clear speed against grouped Steel Path enemies. The catch isn’t cost. It’s time: you need Mastery Rank 14 and a finished Angels of the Zariman quest before Cavalero will even sell you the blueprint.
No Cavia grind, no external adapter to farm. The Laetum’s Incarnon transformation is baked into the weapon from the day you build it. Land 100 weakpoint or headshot kills and Alt-Fire flips it into a full-auto mode that fires explosive rounds with a Radiation blast on every hit.
The Laetum is a Zariman secondary, one of the weapons the Orokin brought along for a maiden voyage that never got its celebration. In stock semi-auto mode it fires Impact and Slash rounds and doesn’t do much to stand out: 160 total damage, a 12-round magazine, 2.5 rounds per second. Fine. Forgettable.
The reason it shows up near the top of nearly every best-secondary list for late 2026 has nothing to do with that base mode. It’s the Incarnon transformation underneath it. Once unlocked, Alt-Fire swaps the gun to full-auto, every round becomes a small Radiation explosion on impact, and the whole thing turns into one of the stronger answers to a room full of Eximus units right now.
How to get the Laetum
You can’t walk up and buy this one on day one. The blueprint comes from Cavalero, a vendor for The Holdfasts syndicate, and you won’t find him until you’ve finished the Angels of the Zariman quest and reached the Chrysalith hub aboard the Zariman Ten Zero. You also need Mastery Rank 14 to equip the finished weapon. If you’re not there yet, this is a later-game pickup, not something to chase right now.
Once you’re standing in front of Cavalero, the blueprint itself is cheap: 3,000 Standing at Rank 0, Neutral, with The Holdfasts. No reputation grind past that point. Building it costs 30,000 Credits, 1 Voidplume Pinion, 5 Voidplume Quill, 20 Voidgel Orb, and 4,000 Ferrite, with the usual 24-hour timer. Rush it with Platinum for same-day access; expect to pay somewhere around 25 to 35 Plat depending on where you check.
The Incarnon side is where the real time goes. There’s no adapter to farm and no Cavia standing involved. That system belongs to the older Incarnon Genesis weapons like Braton and Lato, a completely separate unlock path. The Laetum’s Incarnon is earned per save, on the weapon itself: land 100 weakpoint or headshot kills and Incarnon Form opens up. You’re not done there. Four more evolution challenges stand between you and the full five-tier Incarnon, including Eximus kills and Void Flood missions. Budget a handful of dedicated sessions for this, not one afternoon.
Stats
| Class | Secondary |
|---|---|
| Mastery Rank | 14 |
| Trigger | SEMI |
| Noise | Alarming |
| Fire Rate | 2.5 |
| Accuracy | 16 |
| Magazine | 12 |
| Reload | 2 s |
| Critical Chance | 22% |
| Critical Multiplier | 2.2x |
| Status Chance | 22% |
| Riven Disposition | (0.5) |
| Damage | 160 total |
|---|---|
| Impact | 64 |
| Slash | 96 |
Before you sink Kuva into a Riven for this thing, know the number: Laetum’s disposition sits at 0.50x, one pip out of five. That’s about as low as dispositions go. A Riven roll here is close to wasted Kuva. Put it toward a weapon with better disposition instead.
Builds
Most Laetum builds lean into the Incarnon mode’s crit stats instead of fighting them. Base crit chance sits at 22% with a 2.2x multiplier. That’s a real foundation, not a footnote. The common build layers multishot, crit chance, and crit damage on top of that, then leans on the weapon’s Tier V evolution to push crits further. Players split hard on which Tier V evolution to run. Overwhelming Attrition builds a stacking damage buff off non-crit hits that multiplies with your next crit, and crit-focused builds favor it. Devouring Attrition gives a flat chance per non-crit hit to deal a large bonus hit instead, and it’s the pick for a more status-leaning build. Neither is wrong. Pick based on the rest of your loadout, not on which one sounds better on paper.
Pistol
Pistol
Pistol
Pistol
Pistol
Pistol
Pistol
Pistol| Mod | Effect |
|---|---|
| Galvanized Diffusion | +110% Multishot base, plus +30% Multishot per kill for 20 seconds, stacking up to 4 times |
| Pistol Pestilence | +60% Toxin damage, +60% status chance |
| Primed Target Cracker | +110% critical damage |
| Primed Pistol Gambit | +187% critical chance |
| Hornet Strike | +220% base damage |
| Lethal Torrent | +60% fire rate, +60% multishot |
| Primed Heated Charge | +165% Heat damage |
| Lethal Momentum | +40% projectile speed (Exilus slot) |
For the arcane slot, Secondary Enervate is the pick multiple build guides land on. It procs off non-crit hits and builds toward the Overwhelming Attrition evolution’s guaranteed high-tier crit window, which means you can drop some crit chance mods elsewhere in the build. Secondary Merciless and Secondary Encumber come up as alternates for players leaning more status than crit, and Secondary Fortifier is worth a look for the free Overguard on Eximus-heavy tiles if survivability matters more to you than raw damage.
Reviewed September 2026.
Pros and Cons
Pros
- Ranked S-tier or top-of-class secondary across multiple independent 2026 tier lists
- Incarnon mode combines high fire rate, real crit stats (22% base chance, 2.2x multiplier), and a Radiation AoE on every shot for fast clears against grouped enemies
- Build space supports both crit-focused and non-crit or status builds, depending on which Tier V evolution you pick
- Cheap and fast to get once you’re MR14 and past the Zariman quest line: 3,000 Standing, a 24-hour build, no Plat-locked blueprint
- Incarnon mode’s effective magazine can run up to 216 rounds per charge before you need to reload
Cons
- Riven disposition sits at 0.50x, one pip. A Riven roll here is close to wasted Kuva.
- The Radiation explosion on Incarnon shots carries only a 1x headshot multiplier and can’t itself crit off headshots. Only the direct Impact hit benefits from weakpoint damage, so “just headshot everything” oversimplifies the actual damage math.
- Locked behind Mastery Rank 14 and the full Angels of the Zariman quest line before you can even buy the blueprint
- Incarnon Form takes 100 weakpoint kills to unlock, then four more challenge tiers, including Eximus kills and Void Flood missions, before it reaches full strength
- The base semi-auto mode is unremarkable on its own. Nearly everything players like about this gun comes from the Incarnon transformation, not the stock weapon.
This is a weapon for players who already have Mastery Rank 14 and just need a reason to finish the Zariman quest line. Not a starter pickup. If you want a secondary that can carry Steel Path missions on its own once the Incarnon tiers are unlocked, the Laetum earns its reputation. If you’re still working toward MR14, put it on the list and come back later. It isn’t going anywhere in the meta soon.