I'm working on a mod that requires giving an attack spell to every NPC enemy in the game, exactly how the Bear races have Bone Break Fever attached to all of their attacks (look up Race > BearBlackRace > Attacks > Attack Spell for reference.) This is a hidden 'ability' that causes effects to the player with attacked, and is the exact same case with my mod.

I could edit each race directly and add these spells, but there are two limitations: 1) That would conflict with anything that also edits races and 2) Only one Attack Spell can be specified on an Attack, and I wouldn't want to replace anything there already (again, using the Bear as the example.)

What would be the absolute CLEANEST and highest performance way to add an attack spell to each enemy NPC encountered? Is there a simple way to do this? It would have to trigger during their regular attacks, no matter what they are.

Thank you!