Urza, Lord High Artificer Though making a Construct token is arguably the least broken ability on Urza, Lord High Artificer, its enough token generation for it to score a spot on this list
Not because it is powerful, but because it shuts everything down
Your main play area is divided into the Active Spot where your active Pokmon stays, and the Bench
This is different from Adventure from the Throne of Eldraine set, because you had a choice to cast either the creature or spell version
All the card does is give you information about the opponents hand and replace itself
By allowing it to target your own spells, you can suddenly build around the random element of this card and fill your deck to the brim with obnoxious expensive cards