Hey
Unholy Death Knight Apocalyse minion spawn effectiveness is reduced because out of the 20 seconds the ghouls and Magus around 4-5 seconds of the time is wasted on the summoning animation (magus animation is decent, ghouls are terrible) Taking into consideration that the ghoul require travel time to the target if it moved we can deduce that the spell is possible weaker than intended. Normal ghoul summon also suffers from this, but I guess it is less impactful.
^I have tested this with timers and all and the tooltip states that the summons last 20 seconds. Thank god that the horsemen appear fast and instantly attack.
PS: Try adding a Glyph or something to make Defile more decent/clear looking. Like a green/blue death and decay
Fix the flying + pet summoning issues. It is driving us insane