Caustic Projection

You emit an aura of caustic magic centred on yourself. It eats away at metal and corrodes flesh and bone.

Choose a number of creatures equal to your spellcasting modifier that you can see within 30 feet. For every 6 seconds the creature remains in the aura, they suffer a stacking penalty reducing their Armour Class and To-hit rolls by 1, to a maximum of -10 at the end of the spell’s duration. The creatures take 1d4 acid damage each turn they are in the aura.