Moondragon feels overcosted to me. You get one attack or thwart, and either a block (which you could have gotten from a 2-cost ally), or a use of the ability. I think it's pretty rare you'll be able to get more than three damage out of the ability, which doesn't feel like it's worth more than a block (which, remember, is overcosted in this package). For a net cost of four (3 + card), I'd like to be getting six damage, maybe more, which seems like a tall order.

Maybe for certain scenarios with Villainous minions, enemies with big retaliate (e.g. MODOK) so you're effectively hitting two targets at once, or if you have an especially good Guardian synergy.