Warp Lightning Shield

The warlock surrounds himself with a protective
shield of warp lightning.
Until your next hero phase, the first 3 wounds
allocated to the caster in each phase are negated.
If a fourth wound is allocated to the caster in
the same phase, then the caster suffers D6
mortal wounds and this spell is unbound (the
first 3 wounds allocated in that phase are still
negated).