A standard fire spell; combined with Paralysis in War Crime's only prior recorded casting.
The AI's example of War Crime's single prior use has an Operatic Collective warlord combining Fireball with Paralysis against charging soldiers from a mantid team. The AI calls the choice uncreative but concedes that it worked.
Amplified by War Crime from a circle of power, the spell hit approximately 200 mercenaries at once and set them permanently on fire. They burned, paralyzed and undying, for the remainder of that floor — roughly two weeks — until that season's AI put them out of their misery when the floor collapsed.
A ball of conjured flame.
One of the two spells combined in the example War Crime casting.
Also appears in books you've already read — spoiler-safe to their endings: