I'm trying to build a custom spawn list that controls when certain tags are added. I was wondering if a list of the NBT codes applied by Infernal Mobs could be provided somewhere?

Mod names can be gleaned from the translation files.

https://github.com/AtomicStryker/atomicstrykers-minecraft-mods/blob/1.12.2/InfernalMobs/src/main/resources/assets/infernalmobs/lang/en_US.lang

First one is translation.infernalmobs:mod.1UP=1UP, so "1UP".

Thank you. Quasi-related: Do you happen to know if applying these to Mobs via In Control is possible? I know it can edit NBT codes, but I haven't had much success getting actual results.

Don't know what that is. Getting Infernal Mobs from "outside" the mod would involve saving and loading the map such that NBT tags are re-processed.

That helps lend a little understanding. So you can't slap an NBT value on a mob as it spawns and get Infernal effects? That's an understandable shame. I'll have to remove Infernal then. Such a fun mod though!