In 1v1 formats, its essentially a waste of your mana and your time, but when you have three opponents actively casting spells each turn, Rhystic Study transforms into a powerful draw engine
Quandrix, the Proof, is a 6/6 with Flying and Trample that, on another day, could slip into second on our list
Moderation I like drawing cards, but this is ridiculous
Artifacts have a problem similar to that of creatures, in that putting stories on them made them feel more like the receptacles (books and such) than the stories themselves
Its tantalizingly close to underpowered but actually playable with Harbor Serpent
Those planeswalkers will be rendered useless once they hit the battlefield, since they operate entirely through activated abilities