Oh-ho, this was a tricky one. Well played. Not often you have weapons on this forum.
The answers are Assassin's Blade (No card text) and Fool's Bane (Unlimited Attacks each turn as well)
Here's one that's thematic to the last one, but Probably a lot easier.
5 mana, 3/4 Mech. Divine Shield. (2 answers, 1 change each)
2
I think Auchenai Soulpriest has a better body.
2
Doomguard is riskier because of the loss of cards. It'd be difficult to combine, say, two Power Overwhelming with the Doomguard if you only have fewer than five cards in your hand.