Class damage modification being inconsistent with spell gems

PC, V0.23.1

My Valkyrie Knight (Life) casts shellbust (Nature) on a pulse bat (chaos). This triggers the trait of my plague alchemist (sorcery).

Expected result: The bat will lose X defence, take “X/4…” damage (drain does half the stat loss as damage, halved again due to being sorcery damage on a chaos creature) and then take 2X damage from shellbust (Since shellbust does 200% of the lost defence as damage, and nature damage vs a chaos monster should be unchanged)

Observed result. Drain deals “2…” damage, the bat loses 27 defence, then takes “27…” damage from shellburst. The reduced drain damage I assume was because of a sorcery shield, but shellburst damage being both displayed as ineffective and being half what it should be doesn’t make sense.

Second case: Valkyrie Knight casts shellbust on a nature monster (specifically a pandemonium queen affected by morph: nature)

expected result: Queen will lose X defence, take X damage from drain, and 2X damage from shellbust
Observed result, Queen loses 39 defence, takes 38 damage from drain, and “39…” damage from Shellbust.

The sorcery damage is normal, but shellbust does half damage as if it were a life spell, even though the gem itself had the nature type.

Third case, Valkyrie Knight casts shellbust on a sorcery monster (same fight. Mighty morphin’ Pandemonium Rangers?)

abridged version: The spell did half damage again. Expected, because nature spell v sorcery, but if the spell is ineffective here when cast by a light monster, then it shouldn’t be ineffective against a nature monster.

Then, my imp hexer (nature) cast shellbust (nature) on a sorcery-morphed monster. It lost 50 defence and took 100 damage, even though both the caster and the spell should’ve had a class disadvantage.

Thanks for the information - I think I’ve found the problem!

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