Maybe it could be changed to something like +1 attack per creature for every 10 damage you take, or something like that. So that it didnt matter how many creatures were attacking, but rather just how much damage you take. It would maybe have to be even higher damage taken per attack, but yeah. I just like the idea of doing extra damage from taking damage, so yeah .
This sounds reasonable. Still keeping the whole idea of the card. I was also thinking to modify it so that the AP buff would be temporary much like "dive" effect. I'll give some more thought but i may just tweak it as you suggested.
From "Each time you take damage, your creatures get +1 / +0" to --> "Each time you take
10 damage, your creatures get +1 / +0" (or "For each 10 damage you take, your creatures get +1 / +0"). In that case, I might make this a permanent instead of a shield. Light element has no (non-shield non-weapon) permanents, so it might be cool.
Please tell me what you think about this tweaked version, especially since i made it able to stack with its copies. Thanks for the feedback.