Shield Ally

2nd-level abjuration

Casting Time:1 reaction, which you take when a friendly creature is hit by an attack or targeted by the magic missile spell
Range:30 feet
Components:S
Duration:1 round

An invisible barrier of magical force appears and protects a friendly creature within range who you can see. Until the start of their next turn, the target has a +5 bonus to AC, including against the triggering attack, and takes no damage from magic missile.