If your main goal is to make Legacy more affordable and accessible, however, there are other, better, easier ways to do it that dont involve fighting against WotCs seemingly unbreakable oath
Fortunately, thats why we have Kangaskhan or Hypno, and those decks have significant weaknesses that Mewtwo can exploit: Charizard EX takes a long time to set up without Moltres (which Mewtwo EX can OHKO) and Blastoise EX requires a lucky Misty draw to reliably get its Energy
Psychic Frog is the key detail here
Financially speaking, the EV of playing in Pro Tours just went up
Most classic and modern Doctor Who adventures involve flavorful and memorable settings that will excellently translate into MTG gameplay
It's strong in most mono-Black decks, blink decks looking for lands, ramp decks looking for more ways to ramp out lands in the creature base and midrange decks that have loads of card advantage ETB dorks like this to use and abuse