Larian Studios Forums Divinity - Original Sin Divinity - Original Sin - General Why does my attack vary between 3 and 4 AP?

Noticed the same thing on multiple occasions.
Sometimes an attack from the same char against the same enemy when both did not move goes from 3 to 4 AP. Can't say if there's anything particular happening before (say if the enemy got knocked down, or did move an un-noticeably small way).