A careless bug that i found in this game is when 瑞尔 uses 瞬移 magic when the bridge is broken. the formula is "when MP is greater than 6, then cast 瞬移 magic, and - 6 MP. However, when 瑞尔's HP is 0, you are still able to use this magic.
I think the "true or false statement" should be when "HP > 1 & MP > 6" than activate the magic.