Review: Laetum (U31.5.7)

The Laetum is an MR14 Secondary, one of the new "Incarnon" weapons. Its default form is a fairly ordinary slow-firing Semi-Auto, however headshots will charge up an Incarnon form. When transformed, the Laetum is quite possibly the strongest ranged weapon in the entire game.

NOTE: Angels of the Zariman spoilers have been kept to a minimum in this review, but by nature of its acquisition and upgrade it is not completely spoiler free.

Acquisition

The Laetum Blueprint can be purchased from the weapon vendor on the Zariman. There is no Syndicate Rank requirement for it.

Stats

The Laetum's Default form is solid but nothing outstanding. It is a relatively low Fire Rate Semi-Auto, firing ordinary projectiles. It has very solid Crit at 22%/2.2x, as well as decent Status Chance also at 22%. These combine well with its 60% Slash bias, allowing it to inflict strong Slash procs at a reasonable rate.

With such low Fire Rate, its Reload Ratio is a decent 2.4.

To charge the Laetum's Incarnon form, you must land headshots in Default form. Each extra Multishot pellet counts as a separate headshot. This charges a bar directly below the reticle. After landing 12 headshots (Multishot counts as extra headshots), the Laetum's Incarnon form will be fully charged, though it is available with proportionally reduced ammo at any amount of charge. The form change takes approximately 1 second, and is triggered by pressing Alt Fire.

Incarnon form is a Full-Auto, firing small explosive rounds. It is absurdly powerful, retaining the same solid Crit/Status but dealing 2.5x damage-per-shot, mostly in its small added Radiation explosion. Its Fire Rate is also significantly higher, for an overall drastically higher DPS and proc output.

As standard, the explosion can inflict self-stagger/knockdown. Curiously, Incarnon form is unaffected by Punch-Through - its shots will always detonate on the first solid object it hits.

Incarnon form has approximately 220 ammo at full charge before it reverts to default mode, which is not affected by mods or Ammo Efficiency (e.g. Energized Munitions). The remaining ammo count is shown on the charge bar, slowly depleting as ammo is used. When rapidly using lots of charge, the bar will show the depleted amount using one of the other energy colours.

Augments

None, it's a new weapon.

Evolutions

The Incarnon weapons introduce another new mechanic on top of their Incarnon forms. Each weapon has a series of "Evolutions", which are unlocked by completing an associated challenge. Besides the first, which unlocks Incarnon form, each Evolution has three options. They can be switched around at will at the Zariman's weapon vendor.

As mentioned previously, the first Evolution unlocks Incarnon form, and is the only option for that slot. It is unlocked by getting 100 kills with the Laetum.

The second Evolution is unlocked by killing 8 Eximus units with Incarnon form.

• Marksman's Hand - reduces Recoil by 40%. Default form has fairly high per-shot recoil, and this Evo can make quick follow-up shots, particularly headshots, much easier to land.
• Rapid Wrath - increases Fire Rate by 20%, which is a minor DPS increase. Note that it stacks additively with Fire Rate mods, so is quite small alongside the usual Lethal Torrent.
• Raptor's Chase - reduces the Movement Speed penalty while aiming. This one is purely a personal preference and playstyle choice.

The third Evolution is unlocked by landing 8 headshots with Default form on a Void Angel (new Zariman enemy) without reloading. With a default Mag Capacity of 12, this is very doable with decent aim, and can be made even more lenient by increasing Mag Capacity and Multishot.

• Lethal Rearmament - increases Reload Speed after landing headshots. This Evo is quite useful if you are unable to land all the desired headshots to charge Incarnon form within a single mag.
• Awakened Readiness - provides passive reload-while-holstered effect. This is an effect I am a big fan of, but is a personal preference choice. It only affects Default mode.
• Feather of Justice - gives +60% Ammo Efficiency (60% chance to not consume ammo when shooting) during Aim Gliding and Sliding. Unfortunately, this does not affect Incarnon form. I find it difficult to land headshots while Aim Gliding or Sliding, so would not personally use it, but again this is a personal preference one.

The fourth Evolution is unlocked by completing 12 Ruptures in the new Void Flood mission type (4 rotations worth).

• Caput Mortuum - increases headshot damage by 50%. A simple Evo that rewards aiming with a significant damage boost.
• Incarnon Efficiency - increases Incarnon form charge rate, requiring only 8 headshots instead of 12 for full charge. Makes Incarnon charging much faster, which is the form you want the Laetum in as much as possible.
• Elemental Excess - +20% Status Chance, -10% Crit Chance. These are added after all mods take effect, so can be quite beneficial in the right build - see Evo 5 Devouring Attrition below. (e.g. 40% final Status Chance is increased to 60%, 30% Crit Chance is reduced to 20%)

The fifth and final Evolution is unlocked by equipped an Incarnon weapon in all three weapon slots. At the moment, there is only one Incarnon weapon per slot: Phenmor Primary, Laetum Secondary, Praedos Melee.

• Devouring Attrition - on any non-Crit hit, has a 50% chance to deal 21x damage. This naturally combines with Evo 4 Elemental Excess to focus on a pure-Status build, and can deal some insane damage. This damage boost is separate from Damage mods/Arcanes, and so applies multiplicatively.
• Reaper's Plenty - gives +40% Ammo Efficiency for 6s after landing a headshot. This does not appear to affect Incarnon mode unfortunately, making it largely a dud choice considering the other two options available.
• Overwhelming Attrition - upon a hit that does not Crit or inflict a Status proc, increases Damage by +400% for 20s. It stacks up to 3 times. This Evo is also extremely strong, as even with a high Crit Chance/Status Chance build, unless you are at 80+% with either, it is very easy to stack this absolutely enormous damage boost. It is additive with other +Damage effects like Hornet Strike/Galvanised Shot and weapon Arcanes.

The above are some of my damage calculations for various DA/OA configurations. As you can see, it is a mess and which build comes out on top depends on a lot of factors.

While Galvanised Shot technically offers some very high multipliers, for Incarnon form it only affects direct hits, which is a mere 25% of its total base Damage. As such, though Hornet Strike is on-paper weaker, in effect it is actually better than Galv Shot as it boosts the majority of Incarnon's damage.

Secondary Merciless/Deadhead are far more valuable for DA builds than OA, as OA's damage bonus is additive with them. Keep in mind that DA builds usually have one or two spare mod slots compared to their OA equivalents, as they do not need to slot in Crit. This results in most optimal DA builds beating their OA equivalents for DPS in a vacuum.

Headshots benefit Crit builds more due to the additional Crit headshot damage.

Any equipment that boosts Crit (e.g. Arcane Avenger, Adarza Kavat's Cat's Eye Precept), especially Crit Chance, swings it clearly in favour of a Crit + OA build. Increasing Crit Chance also completely ruins the damage output of a DA build. Note that increasing Crit Chance above 100% also prevents OA from stacking, and anything beyond around 80% makes it somewhat inconsistent.

In particular, the new Cascadia Overcharge/Accuracy Arcanes make a Crit OA build clearly the best if landing headshots, far outclassing the default Secondary Merciless/Deadhead. Such a build will beat just about any DA build, even with the mod slot disadvantage. Keep in mind however that as mentioned just before, OA will not stack if Crit Chance exceeds 100%.

In short, pick the one you prefer. Both DA and OA have very strong builds and deal absurd amounts of damage. Both have their own strengths and weaknesses. Which one is better depends on many factors and should be tailored to your own preferences, playstyle and equipment.

Builds

NOTE: At the time of writing, the Laetum did not exist in warframe.builder or overframe.gg. I created a Laetum in warframe.builder using the Custom Secondary function, both its default and its Incarnon forms. In all cases, the top build represents Default form, while the bottom build is Incarnon form. Unfortunately warframe.builder does not properly reflect the effects of Galvanised mods or weapon Arcanes. During editing, overframe.gg added the Laetum, but it does not allow emulation of the Evolutions, so I have stuck to warframe.builder to use its Rivens for that purpose.

Basic Crit 0-Forma:

These initial builds are made without Evolutions in mind, particularly E5DA and E5OA. For builds with those considered, see further below. The Laetum has a single native V polarity, allowing for a rudimentary build to fit. Depending on the ranks of your mods and mods available, you may not be able to fit in Lethal Torrent.

Viral is of course the standard go-to combo, with its proc being useful on most targets even if its multiplier is poor. Corrosive is slightly stronger in a pure anti-armour role, and notably combines with Incarnon form's innate Radiation to deal super-effective damage against most common Armour types. Corrosive also has the best multiplier against most heavier Infested, notably those on the Cambion Drift who are immune to Viral procs.

Toxin is extremely strong against unarmoured Corpus, ignoring their Shields entirely and striking at their often-weak Health. Organic Corpus in particular are especially vulnerable to Toxin. On the other hand, if you want to prioritise depleting enemy Shields, Magnetic will do so extremely effectively. Again, Incarnon form's innate Radiation is a great complement to these, as it is effective against several Corpus Health and Armour types.

Recommended Setups: Viral vs everything, Corrosive vs Armour, Infested, Toxin vs unarmoured Corpus, Magnetic vs strong Shields

Basic Crit 1-Forma:

One added V polarity allows you to fit in Lethal Torrent, as well as enough space to upgrade one of the Crit mods to its Primed version, provided you have the requisite 60/60 elemental mods to save space.

Recommended Setups: see above.

Primed Crit 2-Forma:

Two added V polarities allows you to upgrade both Crit mods to their Primed versions, which is a significant chunk of extra damage.

Recommended Setups: see above.

Crit 3-Forma:

Another added V polarity and you can start looking at eighth mods. There are a lot to choose from.

A third elemental mod offers a variety of extended elemental combos. Adding Heat to Viral or Corrosive is a strong option, as it synergises well with both of those, both in direct damage and in procs. Similarly, putting together Magnetic and Toxin combines well with Incarnon form's innate Radiation, for a great anti-every-Corpus combo.

Magnum Force is a strong damage boost early on, but becomes outclassed by many other options as you acquire more mods, weapon Arcanes, and Evolutions. Similarly, Augur Pact is very weak but its low Drain can be useful for incomplete builds. A (Primed) Expel mod is very strong, especially as it is an external damage multiplier to most other effects. It is particularly good for amplifying damage-over-time procs like Slash and Heat.

Hydraulic Crosshairs and Sharpened Bullets are conditional Crit-boosting options. Carnis Stinger can be used to maximise Default form's Slash proc output, but is useless for Incarnon form.

Another mod of note is (Primed) Quickdraw. The time required to change form is roughly 1 second, however this is sped up by any +Reload Speed mods. It also greatly improves the quality-of-life of Default form. However neither the form change time nor Reload Time are significant if you are using the Laetum optimally.

I like (Primed) Firestorm to amp up Incarnon form's AoE. While it is not particularly large, the improved anti-crowd capability is still welcome, especially as it already does more than enough damage to single targets.

While Incarnon form cannot natively inflict any Slash procs, Hemorrhage can be used to re-introduce them. Direct hits deal pure Impact with decent Status Chance and Fire Rate, so will get a minimum of Hemorrhage assistance. In the content I've tested against though (up to ~lvl150 Steel Path), Slash procs are not even needed to rip through enemies at that level, especially once Evo 5 is unlocked.

For the Exilus slot, I favour Lethal Momentum for the increased Projectile Speed. Both firing modes fire projectiles that are a little slow, and the increased speed can be helpful beyond close range. Ammo Mutation is not really necessary as a well-used Laetum spends so little time actually consuming ammo. Steady Hands to reduce Recoil can be useful on Default form to make follow-up headshots easier, but there is also an Evolution for that.

Recommended Setups: see above. Also consider: Viral + Heat vs everything, Corrosive + Heat vs Armour, Infested, Magnetic + Toxin vs Corpus

Galvanised Build and Arcane

Galv Diffusion is an auto-include as always, and is especially useful for charging Incarnon form. Each Multishot pellet counts as a separate headshot, so with maximum Galv Diffusion + Lethal Torrent, you can potentially recharge Incarnon form in just 3 headshots (2 with Evo 4 Incarnon Efficiency).

Galv Shot seems like a strong direct hit damage boost for either firing mode. Both have two damage types at base, and can be given two extra with elemental mods (three in the case of Incarnon form, with the Slash procs from Hemorrhage). However, Galv Shot does not affect Incarnon form's AoE, which is where the majority (75%) of its damage is. As such, I generally think Hornet Strike is the better of the two if you have to choose, as it will add more overall damage.

Galv Crosshairs is a strong, if flawed option on an E5OA Crit build. Obviously, boosting Crit on a Crit build is great for more damage, and the Laetum already wants to be going for headshots to charge Incarnon and deal maximum damage. However, exceeding 100% Crit Chance can make OA impossible to stack, since it will only stack on a non-Crit hit. Thankfully, since Galv Crosshairs only activates while aiming, this can be solved by simply not aiming in when you need to stack/refresh OA.

There are several factors to consider in Arcane choice. Secondary Merciless and Deadhead are both low-fuss damage boosts that are easy to stack. Merciless stacks on any kill, while Deadhead stacks faster with headshot kills, lasts longer, and offers higher peak damage with its headshot damage increase. The +Reload Speed from Merciless also reduces form change time slightly. However, they are less valuable on an E5OA, as they stack additively with OA's far larger damage boost.

Cascadia Overcharge and Accuracy both offer conditional +300% Crit Chance. As mentioned in the Evolutions section, these are the best Arcanes that an E5OA build can use for pure damage output. They offer noticeably higher peak damage than Merciless/Deadhead. Note however that alongside a +Crit Chance mod like (Primed) Pistol Gambit, it will exceed 100% Crit Chance, thus making E5OA impossible to stack normally.

Obviously, these two Arcanes are a no-go on an E5DA build.

Cascadia Empowered is noteworthy as it will forcibly stack E5OA, even if your Crit/Status Chance exceed 100%. However, the extra damage it deals is extremely small compared to any of the other Arcanes, so you are trading peak damage for reliability. 

EDIT 12/05/22: U31.5.8 just removed Cascadia Empowered stacking E5OA, and given its total lack of damage, it is no longer worth using in an E5OA build.

Interestingly, E5DA can actually apply to the Cascadia Empowered damage instance, giving it a 50% chance to deal 15,750 damage of the appropriate type. Even so, it does not remotely compare to the damage boost offered by the standard Secondary Merciless/Deadhead.

Evolution 5 Builds

Taking Evo 5 into account, Incarnon form especially reaches some ludicrous damage numbers. The above builds emulate Overwhelming Attrition, using a Riven of +1420% Damage to reflect Hornet Strike + maximum E5OA. A more optimised build can reach much higher numbers easily.

A Devouring Attrition build is just as, if not even more, absurd. These above builds again use a Riven to emulate the DA bonus in the form of Damage vs Grineer, while also covering the Arcane as warframe.builder does not currently calculate it.

Keep in mind that neither of these builds are totally optimal - they just give an idea of how insanely strong the Laetum is.

My Builds

This is my typical build, a Viral + Heat Crit build with E5OA. I run Cascadia Empowered to ensure E5OA stacks. The small damage boost it offers compared to other Arcanes is a non-issue as the Laetum Incarnon deals so much damage anyway. I've started using Cascadia Accuracy for this build to spike its damage through the roof when used correctly.

This is the build I use with E5DA. It can of course be optimised by switching Galv Shot to a Primed Expel, but I don't like Faction damage mods.

I favour the following Evolutions:

• Evolution 2: I use Marksman's Hand to make landing multiple headshots in Default form much easier.
• Evolution 3: I use Awakened Readiness, though none of the three are significant to me.
• Evolution 4: I typically use Incarnon Efficiency. Incarnon form is so strong that Caput Mortuum's extra damage is not necessary (but is very fun!). Since I usually use OA, Elemental Excess is suboptimal.
• Evolution 5: I typically stick to OA, as it is not as vulnerable to +Crit Chance effects in the same way DA is.

Combat Use and Summary

The Laetum's default form is solid, but largely unexceptional. It deals above-average DPS, and can inflict strong Slash procs with reasonable regularity thanks to its majority Slash base damage. As such, it fares reasonably well on its own against fewer heavier enemies.

Naturally, its low Fire Rate is most problematic against groups. While it kills single weaker enemies with ease, it is slow to kill large crowds of them, especially without Punch Through.

Incarnon Form is one of the most powerful weapons in the game. Even without Evolutions, it has a very strong base stat spread putting it among the top Secondaries for sheer damage output. Taking into account its incredible Evo 5 options, Laetum Incarnon form outclasses just about every other weapon in the game. It tears through basically any enemy you put in front of it, even those with extremely tough armour.

Incarnon Form is weakest against groups, though I use "weakest" very loosely. Its decent Fire Rate and small AoE allow it to chew through large groups of enemies quite quickly. However, it is not as efficient against them as traditional meta AoE weapons.

Both forms fire somewhat slow projectiles, which can make longer ranged combat a lot more difficult.

Ammo is typically a complete non-issue. Ideally you want to be using the Laetum in Incarnon form as much as possible, which itself does not consume ordinary ammo. Default form, which is otherwise a normal weapon, is only really used to land the headshots necessary to charge Incarnon. Done properly, this can be achieved in just 4-5 shots (even fewer with Incarnon Efficiency).

As is discussed further below, the Laetum's Default form is fairly pedestrian and not too special besides its access to (some very strong) Evolutions. Depending on playstyle and enemies, it can be troublesome landing the couple of headshots before the weapon can become really worth using. As such, the Laetum can pair well with Frames whose abilities can slow hold enemies in place such as Harrow and Vauban, or notably the Scourge Speargun whose Alt Fire allows for easier headshots.

Overall, the Laetum is a conditionally extremely powerful weapon. Its default form is largely unexceptional, being only a solid Semi-Auto. Incarnon form packs some of the strongest firepower in the entire game, and will tear through just about anything put in front of it. Evolutions add an extra element of customisability, with several options depending on playstyle and personal preferences.

The sheer strength of Incarnon form makes it a sight to behold, and provided you can land a few headshots to get it started, I highly recommend anyone to acquire or at least work towards the Laetum. Though Evolution 5 is time-consuming to unlock, it skyrocket's the Laetum Incarnon's already amazing damage output to utterly ludicrous.

Scores

NOTE: Scores are based on reliably having access to Incarnon form, though Default form is still discussed. 

Vs Trash Mobs: 4.5/5 - Default form is slow-firing with no AoE, so naturally fares poorly against groups. Incarnon form is much faster firing with a small AoE. It effortlessly kills weaker enemies and can chew through large groups of them with ease, though perhaps not at the speed of the meta AoE weapons.

Vs Unarmoured Heavies: 5/5 - Incarnon form having the highest DPS of any weapon in the game makes this an easy top score. Default form is above-average in this regard, but not amazing.

Vs Armoured Heavies without Forced Slash: 5/5 - Default form is a decent Slash proc weapon given its solid stat spread. While slow-firing, any Slash procs it inflicts are likely to be extremely strong, and just one or two alongside a few Viral procs can deal massive damage to armoured enemies. While Incarnon form cannot naturally inflict Slash procs, its insane DPS and plethora of other procs can eat through even the toughest enemies effortlessly.

Vs Armoured Heavies with Forced Slash: NA/5 - While it will not get maximum benefit, Incarnon form can make use of Hemorrhage to inflict Slash procs with its pure-Impact direct hits. In the content that I typically play though (maximum lvl ~150 Steel Path), it is not at all necessary and you are probably better off just adding more elemental damage.

Vs Variants

None.

Competitors

There are a number of other decently strong Semi-Auto Secondaries, and compared to them the Laetum's Default form is nothing too special. Thankfully, it is not the form you want to be spending more time using.

The MR12 Akvasto Prime is a fairly strong Semi-Auto. It has much lower base Damage than the Laetum's Default form, but makes up for that with higher Crit Multiplier, far higher Fire Rate, and a shorter Reload Time to compensate. The AkvastoP comes out noticeably ahead of Default form for DPS and Status proc output.

The MR14 Knell Prime is another weapon that rewards headshots. Though it has very poor Slash bias and low base Status Chance, upon landing a headshot the KnellP temporarily far outclasses Default form for sheer damage output thanks to its (temporary) infinite ammo, higher Crit Chance and Fire Rate, and additional stacking buffs.

A Secondary Tombfinger Kitgun is a another strong Semi-Auto, this time with an innate AoE. Due to the wonky stat screen formatting, I have not included those stats in this image. A Tombfinger has higher base Crit/Status spread than Default form (25% Crit/Status Chances), which can be further enhanced depending on parts used. This example Crit-focused build loses out slightly in Fire Rate and Status Chance (base Damage is superior due to the not-shown 89 AoE Radiation damage), but far outclasses in direct damage.

Finally, the MR14 Tenet Spirex is also a great Semi-Auto with a small AoE. Again, its AoE of 80 Heat damage is not shown, which combined with the innate Sister bonus, give it a far superior per-shot stats. This time, the TSpirex is the one with overall worse quality-of-life, though its Reload Speed buff on headshots does help. Despite this and a total lack of Slash in its base Damage, the TSpirex is a largely superior weapon to the Laetum Default form.

I'd consider all of these weapons as good as, if not superior to, the Laetum's Default form in a vacuum. However, the Laetum of course gets access to a wide variety of power-ups in its Evolutions, most notably Evo 5 giving it a massive power boost. With either Overwhelming or Devouring Attrition fully active, the Laetum's Default form will beat any of the aforementioned weapons (except perhaps the KnellP) for on-paper, single target DPS. More importantly, after landing a few headshots, the Laetum can transform into its Incarnon form.

No other weapon remotely compares to the Laetum's Incarnon form for raw damage output, especially once Evolution 5 is unlocked. It far outclasses pretty much every single Secondary (and almost all Primaries for that matter) for on-paper single target/small AoE DPS.

Rivens

As a new weapon, the Laetum starts at a minimum 1/5 (0.5) Riven Disposition. I fully expect it to stay at minimum as its Incarnon form is one of the most powerful weapons in the game.

+Damage/Multishot are good stats for an E5DA build. +Multishot/Crit Damage are ideal for E5OA. +Elemental Damage can be useful to save a mod slot. +Faction Damage can be a strong extra damage multiplier, especially for damage-over-time procs like Heat. It is most useful against the Grineer, who are by far the toughest of the three core factions. +Fire Rate is a solid DPS increase, though will result in Incarnon form draining faster. +Mag Capacity/Reload Speed can be nice quality-of-life for Default form, but do nothing for Incarnon. +Projectile Speed can be helpful for longer-ranged combat. +Punch Through is nice for Default form, but offers nothing to Incarnon.

-Impact/Puncture/Slash all have value. Impact is a terrible damage type and underwhelming proc, so it is no big loss removing it (except for worsening Hemorrhage). -Puncture has no effect so is ideal. -Slash is suboptimal for Default form which can use its Slash damage to inflict strong Slash procs, but has no effect on Incarnon. -Crit Chance is ideal for an E5DA build, and -Crit Damage is not terrible in such a build. -Faction Damage to the weaker factions (Infested especially) is quite manageable, and for the Laetum especially is pretty much ignorable as it deals so much damage already. -Mag Capacity/Reload Speed have no effect on Incarnon form, but can be detrimental to Default form when still charging Incarnon. -Ammo Max is pretty much a non-issue. +Recoil is no problem if you handle recoil well. -Zoom is ideal for close quarters.