Since the tribute is also not an activated effect, there is no way to stop it unless your opponent has a card that stops you from Summoning monsters in general
Supporting and Generating Energy for Mewtwo EX Is Easy To Do With how Mewtwo Ex's biggest move works, it needs to be supported with other cards to do damage consistently
Not because the defeats were particularly humiliating, though they were, but because the entry into these universes attracted a terrible and highly obnoxious menace from each one that they feel ashamed of having brought to the universe in the first place
With one of the lowest pull rates in the set, it stands as the ultimate grail for collectors
This means that you'll need to draw each card automatically to your hand in earlier entries and deal with some unattractive UI decisions that can leave some scratching their heads
You can only use 1 of the following effects of "AssistYummy!" per turn, and only once that turn