Despite requiring colorless, the Seer is arguably easier to cast in a lot of situations, and the fact that the opponent doesn't get their card back until they kill the Thought-Knot Seer is kind of a big deal
This post is a bit late, but that has the benefit that I have testing results with a number of these cards, so you can get my initial impressions
To embark on your Pokmon card adventure using vanity slabs, gather your deck of Pokmon cards and an eager opponent
For this reason, Mewtwo has been regarded as the strongest Pokmon
That ability is "When the last defense counter is removed from this permanent, exile it, then you may cast it transformed without paying its mana cost." (4/14/2023) As a Siege enters the battlefield, its controller chooses an opponent to be its protector