People are going bonkers over this, but how exactly are you going to get it back from your deck after throwing 3 buffs on it? Do you expect to consistently draw it? Count again how many cards you actually see over the course of a game normally and do the math.
And you have to even draw it for the first time. How often does Kelaseth Rogue get him by turn 2? And you expect this to show up every game for you to buff, THEN show up again and again after being shuffled back in?
This is a mirage of power. 70% of the time you will never see it again after the first time it's destroyed. Card is awful.
It's good but not game-winning because it's a 1-mana weapon and Blizzard obviously tested this already. With Deadly Poison, it's a 3/3 weapon for 1-mana which is only ok in the late-game. With Envenom Weapon, it can destroy 3 minions but Rogue's health is a problem. 1-attack means Leeching Poison is useless, unless you're willing to play a weapon Rogue that revolves around a 1-mana legendary weapon.
And that's not even going into Rogue's spells. Leeching Poison, Envenom Weapon, Tinker's Sharpsword Oil, and Deadly Poison all combo togther into making it a monstrous weapon that will clear the way from whatever's stopping your minions, heal you (one of Rogue's biggest problems), and can easily deal a ton of damage over the game.
0
0
0
The clue is in the name: GREEDstone.