rare hex necromancy witch 

Patron pacts

Cast [R] somatic; Trigger An ally uses a reaction to grant you a beneficial effect during a combat encounter.

Range 30 feet; Targets 1 ally

You're unable to leave any debts unpaid. When an ally supports you in a fight, you offer assistance in turn for the favor. The triggering ally gains 12 temporary Hit Points for 1 minute.

Heightened (+1) The temporary Hit Points increase by 4.

Dark Archive, page 159.