Its not a hard counter to Mewtwo, but if you get set up quickly you can win that matchup
The real payoff is the second ability, which rewards you for connecting with your biggest attacker
You really want to be playing this card alongside a bunch of other spells that can manipulate lore counters, giving you as much control over your abilities as possible
If the spell is a permanent spell with targets, such as an Aura, you may also choose a new target for that spell
This time around, however, I found myself interested in the physical trading card game for the first time since I watched friends play it in high school
Even in a mono-black deck with lifegain synergy like Vito, Thorn of the Dusk Rose, cards like Mutilate are just going to be more consistent as a board wipe