Azyrite Halo

This circlet of Azyrite power lashes out at the enemies
of the faithful.
Pick a friendly STORMCAST ETERNAL unit
wholly within 12" of the caster that is visible to
them. Until your next hero phase, each time you
make an unmodified save roll of 6 for that unit,
the attacking unit suffers 1 mortal wound after
all of its attacks have been resolved.