While it doesnt explicitly feature a Trainer, this card showcases Mew in its VMAX form against a void-like, all-black background accented with gold and pink outlines
For one mana you can tap Fluttershy and put a +1/+1 counter on each creature with a tail controlled by a single player, then "stare down" one creature
This allows me to give a fairly comprehensive overview, noting strong cards, decent cards, potential long-term contenders, and then shutting down cards some people will perceive as good
And if you manage to pay Emrakul, the Promised End's hefty 13 mana, then you can make weird things happen during your opponent's turn as you take over for them
We will definitely be coming back the next time we are in town
It gets even better if your deck is built around the popular archetype of casting cards from exile