When Power Blast is used, the user will first charge the attack (Anna readies her bow, while Matt assumes his charging stance) as massive amount of wind blows out of the user's weapon. Then Anna fires her arrow and gets knocked back by the immense recoil, while Matt will charge right into the crowd, similar to Swift Slash.
Power Blast functions similarly to skills such as Bullet Hell in that only the primary takes full damage, while other foes that are hit take one third of total damage.
Epic Battle Fantasy 4
Limit Break! Targets all foes, but damage is centered on one. Element and effects depend on current weapon.
This Limit Break was previously dubbed "critical shot" and was possibly going to be a Limit Break exclusively for Anna.