It does not have to be a legal card in the format you're playing or a part of your Draft or Sealed pool
The one downside the card has is its fairly inefficient stat-line, but honestly, given how strong this is, that hardly matters Cursing an opposing creature isnt the most powerful thing in the world, but when you Bargain this does upgrade your board and downgrade your opponents reasonably effectively
Put a +1/+1 counter on target creature
Wizards isn't about to start banning these cards willy-nilly - in fact it's quite likely that none of them are on the verge of getting the chop
Esoteric Duplicator Esoteric Duplicator requires lots of mana, but the reward of copying oodles of artifacts makes up for it
Be sure to check out IGNs existing coverage of the new day-night cycle as well as new mechanics like Disturb, Decayed and Coven