Here's another first-draft card, Wand of Polymorph. I think it's still a little sparse and needs more fleshing out, but then that's nothing new. The image in the card is just a filler from DeviantArt. The rest is all done in Inkscape. Note the rarity icon in the lower left corner. A player must roll at least a 4 out of 1d6 to earn this card after drawing it from the item pile. As a wand it has multiple charges: 3 of them to be exact. Whenever the card is used it is turned 90°. After the third use, the wand will be discarded.
Transformation has a few special rules. Characters can be transformed into monsters, monsters into other monsters, or items into items of the same kind. Monsters and items polymorph permanently; you discard the original. Characters on the other hand take on the monster card and have that monster's base attributes and special abilities/attacks, at the loss of their own. Anything the character had on a Skill card, however, remains intact. A character can revert to their original form by polymorphing again or breaking the spell by other means.
Polymorphing will also be caused by the Polymorph Trap card. I believe it will have a corresponding rarity. Some magic items will have trap or obstacle equivalents. For example, the Wand of Teleport Away and Teleport Trap cards will be twinned in this way.