I made the mistaken assumption in the previous version of this post that rending stacks would correlate directly with soulblaze stacks. As the patchnotes have been clarified to say it has a 20% cap, I thought I’d run the numbers again to get an idea of how impactful the blessing is likely to be.
Method of testing values:
- Simulate max stacks of penetrating flame on a target giving 20 rending with one stack of t3 Uncanny Strikes, on a sword with otherwise neutral perks.
- Barebones pysker build to get venting shriek with creeping flames, but carefully avoiding all damage buffs to get constant values.
- Selection of units with each of the armor types: Sniper for Unarmored, Pox hound for Infested, Shotgunner for Flak, Rager for Maniac, Reaper for Unyielding, and Crusher for Carapace.
- Apply 6 stacks of soulblaze with Venting Shriek from above 85 peril, take note of base damage ticks, then reset everything.
- Apply 6 stacks of soulblaze with Venting shriek, but this time building 1 stacks of t3 Uncanny Strikes on a different mob, take note of damage ticks.
- Possible Issue: 6 stacks is a low value and its damage is likely to be quite rounded, and so working out damage boost % is going to be vague, but higher stacks kill mobs too quickly and 6 stacks is still good enough for rough estimates.
Results:
- Infested: 31 base, 31 w/ 20 rending (0% boost).
- Unarmored: 37 base, 37 w/ 20 rending (0% boost).
- Flak: 37 base, 38 w/ 20 rending (3% boost).
- Unyielding: 37 base, 38 w/ 20 rending (3% boost).
- Maniac: 25 base, 26 w/ 20 rending (4% boost).
- Carapace: 3 base, 8 w/ 20 rending (167% boost).
My interpretation
The impact of the blessing is tiny, except against crushers. The 0%, 3%, and 4% boosts are much lower than pretty much ever other boost that weapons get from any other blessings that increase damage. Given that rending above 100 effectively gives 25% of its value as a damage buff, I’m guessing the 3% (actually 2.7%) is just a result of rounding, and that it will bottom out at 4% on every target that isn’t either unarmored or infested.
The impact verses Crushers is better. However, the Carapace damage, while improved, is mostly because without rending soulblaze starts with a 0.1 coefficient. Even with the boost from rending it is still a very very slow way to kill them. I tested against a Crusher again, but this time with 15 stacks, and found they take 12 damage per tick without rending and 36 damage per tick with 20 rending. Given they have 3600 hp on damnation, it would take 15 stacks of soulblaze with Penetrating Flame about 1 minute and 15 seconds to kill one. This is without any other buffs (though even if you somehow got enough buffs to double your damage it is still about 37 seconds, which still isn’t fast). That time also ignores the setup time to get up to 15 stacks and assumes that it is refreshed several times to maintain the 15 stacks and debuff. It is hardly going to evaporate a pack of crushers, and will likely remain one of the slower ways to kill them compared to most other options. The old trick of using t4 uncanny on a melee will remain by far the most optimal way for a Purgatus to deal with a pack of crushers. Thus a melee with uncanny will remain a necessary part of a good Purgatus loadout anyway, rending penetrating flames biggest benefit more or less redundant.
Conclusion
The new Penetrating Flame blessing will have a tiny impact to slightly improve Purgatus damage against gunners and elite targets, will help slightly against crushers but won’t trivialize them, and won’t have any impact at all against chaff and some specials. It will be better than the no boost at all offered by the currently available Purgatus blessings*, but it isn’t going to ‘break the game’, at least no more than is currently possible with a well played Purgatus build. [*Warp Nexus is effectively a damage boost, as the extra crits apply stacks faster, moving you up the damage curve faster which results in more damage.]
As far as your own damage output goes, it would be better to just have another perk instead of this blessing, as 25% damage to a single armor type would give significantly more value. Any blessing that is worse than a perk is probably not worth taking.
However, given that the rending is very likely applied to the target as a debuff, which will also increase your teammates’ damage against those targets (by amounts entirely dependent on the weapons they are using), it will mostly function as a support blessing to help your whole team a little. In most situations it will be about a 4% damage increase for teammates against flak, maniac, and unyielding, 0% against infested and unarmored, and some amount more (up to 200% if they start with a 0.1 coefficient, like soulblaze) vs crushers.
My own guess is that Nexus + Blaze Away will become the new Purgatus meta. Though that depends on exactly how Blaze Away is implemented, even the worst implementation is likely going to give more value than Penetrating Flames.
Unknowns
It remains to be seen whether and how this rending debuff will stack with other rending debuffs. Whether it even gets applied if a different Psyker already owns the soulblaze stack. Whether it can still be applied to a target with more soulblaze stacks than the Purgatus’ cap. And whether it is applied by other sources of soulblaze (Perilous Combustion, Creeping Flames, Wildfire, etc).
Sienna eat your heart out Psyker is the real pyromaniac