With it being one of the last Mewtwo cards released by Wizards of the Coast before they no longer were in control of the game, it's a piece of nostalgic history that demands a high value.
1 Inga and Esika
The tax makes it good against spell-focused decks, while first strike gives it legs against opposing creature strategies
The creature with augment will change the creature's name as well as its power and toughness
Especially given the presence of cards like Dark Ritual, four is easier to hit, and even in fair decks, that one turn really does make a large difference. That took care of Aarakocra Sneak, Stirring Bard, and Vicious Battlerager
The recommendation weakens if sealed supply returns in size, if the top-card demand cools, or if overseas pricing runs far above Japan without a condition or sourcing reason