Stop dreaming about stealing the whole board or something, this is a 5 mana card that needs to be combined to have any effect. It will probably steal a single minion for 6 or 7 mana, which is not bad but not OP either. I don't think this card will see much play.
This card will make Hearthstone lose 2 million players.
Nah, aggro is fast. You drop meaningless on 5th, with only rogue having backstab / vendetta to single-removal a minion, you're dead. Galarogue could abuse this - gala this and/or kronx, 6/7 mana combo.
Vs slower decks you wanna keep it for aoes, small ones at 3 (breath, storm), sw:ruin at 4.
And it doesn't trigger plagues, so it's mostly gonna be singular, while mage/shaman have more options (rolling ball, lightning breath).
Great card, not AS hyped, but certainly 4-4.5 star on its face.
It's a good card for control warrior, priest and control shaman as these are the only classes that have really cheap removal spells (Shield Slam, Torrent, Shadow World: Death), but not OP as it is a bit situational