Thrice-blessed hull

Use this Stratagem at the start of your opponent
Psychic phase. Select one HALLOWED model
from your army. Until the end of the phase, that
model gains the following ability:
'Thrice-Blessed Hull (Aura): While an enemy
PSYKER unit is within 12" of this model, each
time a psychic test is taken for that unit and that
test is failed, that PSYKER unit suffers Perils of
the Warp.'