Sword Oath is changed so that it is a new stance where the sword is used with two hands, and the shield stays on your back.

It now increases the damage you receive (compared to the baseline with no oath active) but also greatly increases the damage you output.

In this stance certain actions are unavailable (shield lob, shield bash, shield swipe) but some new sword arts/techniques become available that can only be used during sword oath.

New move examples could be a ranged attack like Cloud's blame beam where you bash your sword on the ground and a shockwave travels in a straight line; a new circle slash type move to hit enemies around you like a whirlwind; a new combo starting with fast blade but ending with two new attacks; a new evasive maneuver perhaps. Anyone got ideas?