Once you announce that you're casting Mutual Destruction, players can't try to remove your permanents with flash to make it lose flash until you're done casting it
However, despite the Power tag, I would not put Timetwister in the broken bucket, and even the venerable Time Walk is at least debatable
In the current Pokemon Pocket metagame, Poison isnt a top-tier archetype, but you can create a strong lineup with the Grimer, Arbok, and Muk trio
It's the perfect card for Crime decks, and combined with Freestrider Lookout especially, gives Crime decks a consistent way to fuel the ability
I even get to play Elvish Piper and Sneak attack to help cheat Morophon into play which is super cool
For three mana, Ghen is a 2/3 Human Wizard with an activated ability that allows an enchantment to be sacrificed for three mana, putting another enchantment from your graveyard directly into play