Tidal Shield

You conjure the force of the tides to gain a +4 circumstance bonus to AC until the end of your next turn. Any allies adjacent to you during the duration gain a +2 circumstance bonus to AC as long as they remain adjacent to you. You can Sustain the effect to a maximum duration of 5 rounds. When a creature receiving a circumstance bonus to AC from Tidal Shield would take damage from an attack, as a reaction, you can reduce the damage to that creature by 40; after you do so, Tidal Shield ends.