Exorcism spirits do not choose ethereal and invulnerable units to attack. However, if their already chosen target turns ethereal or invulnerable afterwards, they ignore the status effect and continue attacking it, despite being unable to damage them.

1. Be ethereal or invulnerable
2. Enter Exorcism's area
3. Check if the ghosts attack you
4. Now do the same again but swap 1 and 2 (first enter area, then become ethereal/invulnerable)

Result: When entering the Excorcism AoE while already ethereal or invulnerable, the spirits completely ignore you and never attack. However, when you first enter the area, and then turn ethereal or invulnerable, then the spirits won't stop attacking you, until you leave the area or until the caster steers them away

Expected: When the spirits' current target turns invulnerable or ethereal, they should stop attacking it after they finish their current attack on them.