If I have a Mickey Mouse & Minnie Mouse – Adventuring Duo in play, can I shift another Mickey Mouse & Minnie Mouse on top of them?
No. While that dual-named character matches the names for the Duo Shift ability, Mickey Mouse & Minnie Mouse is still only 1 character. With Duo Shift you must shift on top of two characters stacked.
Official set release notes — Attack of the Vine!
If I use Duo Shift to play Mickey Mouse & Minnie Mouse – Adventuring Duo on top of a dry Mickey Mouse and a drying Minnie Mouse, what happens? What if the Mickey Mouse they’re shifting onto is ready but the Minnie Mouse is exerted?
If you shift on top of a dry character and a drying character, the shifted character will be drying. If you shift them on top of a ready character and an exerted character, they’ll be exerted. Piercing Attack / Omnidroid – Ultimate Iteration Piercing Attack
Official set release notes — Attack of the Vine!