Gift of Change

If successfully cast, pick one enemy unit
within 18" of the caster and visible to them.
That unit suffers a number of mortal wounds
based on the chart on Kairos's warscroll. If any
models were slain by this spell, before removing
the first slain model, you can add a Tzeentch
Chaos Spawn to your army and set it up within
3" of the slain model's unit.