Calls down a Grand Cross in a 7x7 area around the targeted cell. Any Demon family and Undead property monsters entering the area of the effect suffer Holy property damage of MATK*SkillLV per wave. Waves occur approximately every 3 seconds and each wave appears to hit SkillLV times.
Therefore, there is a certain maximum number of waves than any one monster can be affected during the duration of the spell (there will be less waves if the monster enters late or is knocked back out for any reason).
As it creates an effect on the ground, Magnus Exorcismus cannot stack with other ground effect skills (e.g. Pneuma and Safety Wall).

Summons a purifying cross on the ground to inflicts 100% MATK magical damage on an enemy once per 3 seconds and 130% MATK magical damage per hit for Devil, Immortal, Dark and Immortal targets.
Consumes 1 Blue Gemstone.