Abel says you may discard a good enhancement from hand to protect Cloud heroes from special abilities on evil cards except discard.
Colosseum says negate all protect abilities on cards in the field of battle.
So here's the question is Coliseum stopping able from discarding a card to protect Cloud Heroes? It sounds to me like the discard ability is what's doing the protection and that is outside of battle so Coliseum doesn't work right?
The way I take it is Coliseum Target's cards that protect cards in battle. Able is not doing the protecting. The card that I discard is doing the protecting. So his protections still works I think.