If you can remove their threats, youll eventually find a source of card advantage to put you over the top
It was included on the only Ultramarine-themed card shown during the presentation, and it allows players to field copies of a newly summoned creature for the cost of two additional mana of any color
It becomes a 2/3 right away, with the promise of more
This is inherently powerful stuff we're dealing with so watch out for all those artifact and bird token generators
These are all of the mechanically unique regular Mewtwo cards from Base Set up until Scarlet & Violet 151 (this excludes reprints, multi-prize Mewtwo cards and specially named cards like Rockets Mewtwo)
Still, I'd recommend that if you want to upgrade Elven Empire with another precon and without serious budget constraints, Guided by Nature is a good step in the right direction