Shield Block

•1 immediate action, Personal, Instantaneous
As an immediate action, you can grant
an AC bonus to an adjacent ally equal
to your shield’s AC bonus + 4. You
apply this bonus in response to a single melee
or ranged attack that targets your ally.
You can initiate this maneuver after an
opponent makes his attack roll, but you
must do so before you know whether the attack
was a success or a failure.