You want to always be attacking with Mirri, since it prevents all but one creature from blocking, allowing you to swing recklessly with the rest of your creatures
The value of Mewtwo legendary cards can vary depending on the specific card and its condition
First thing to look at is the incredible versatility
You can cast that card by discarding a card instead of paying that cards mana cost
Mono-Red Phoenix has a lower ceiling but is more consistent
Ian Malcolm, ChaoticianIan Malcolm, Chaotician tips his toe into the chaos pool, giving everyone access to every one else's cards one at a time, and only if someone draws more than one card per turn, though if you stuff your Ian Malcolm deck with cards like Dictate of KruphixDictate of Kruphix, Howling MineHowling Mine, and Temple BellTemple Bell, you can reliably grow the pile of extra spells you can cast