abjuration cantrip 

Traditions arcane, divine, occult, primal

Cast [>] verbal

Range 30 feet; Targets your eidolon, or a creature with the minion trait under your control

Duration until the start of your next turn

You extend your aura, as a magical shield that protects your eidolon or minion. The target gains a +1 circumstance bonus to AC until the start of your next turn. You gain the following reaction; after using the reaction, the spell ends and you can't cast protect companion again for 10 minutes.

Life Block [R] Trigger The spell's target would take damage; Effect Reduce the triggering damage by 10, but you lose 5 Hit Points. Even if this reduces the damage to 0, the target still takes any effects that would come with the damage, such as the poison on a viper's fangs Strike.

Heightened (+2) The reaction reduces the damage by another 10, and you lose 5 more Hit Points. If you want to lose fewer Hit Points, you can choose to lower the damage reduction and HP lost to what any lower-level version of the spell could do without lowering the spell's actual level.

Secrets of Magic, page 123.