Catalyst

Through its synaptic conduits, the Hive Mind reaches
out to infuse the organisms under its control,
invigorating their metabolisms with such unnatural
vitality that they can ignore the most grievous of
wounds.
Catalyst has a warp charge value of 6. If
manifested, select a friendly TYRANIDS unit
within 18" of the psyker. Until the start of your
next Psychic phase, each time that unit loses a
wound, roll a D6; on a 5+, the damage is ignored