This is a new mechanic in the vein of Living Weapon and For Mirrodin, giving you a free body that your Equipment attaches to automatically on entry
As for the bounce package, you are running all the best bounce cards: Merlin - Goat and Merlin - Rabbit as your bounce targets, Madam Mim - Snake and Madam Mim - Fox as your bouncers
Yzma - Conniving Chemist focuses on card draw for Amethyst decks, as exerting her allows the player to draw until they have three cards in their hand
Illumineer's Quest Cards With Ursula's Return, new cards were introduced for the Sea Witch to play against Illumineers
Shes got an ability that sort of sounds like it could be a negative (you have to banish either her or two other characters of yours), but works incredibly well when you pair it with certain Merlin cards
Nomura worked as the main character designer on the 1997 game and contributed to the narrative as well