pf2e.fyi
From Pathfinder Impossible Magic, which isn't enabled.

Collateral Reinforcement

FEAT 6
Activity 1 action

With a combination of bony armor, extra flesh layers, and tactical incorporeal phasing, you protect your thralls from collateral damage. For 1 round, your thralls become immune to area and splash damage.

Pathfinder Impossible MagicORC