The first and most obvious is the Charizard card from the base set
When Protean Hulk was unbanned I picked up a copy and eventually added Flash, Phyrexian Delver, and other combo pieces to a deck I had built around The Mimeoplasm
2: Create a 1/1 blue Ninja creature token with "This token can't be blocked." 7: You get an emblem with "Whenever a creature you control deals combat damage to a player, search your library for a blue or black creature card, put it onto the battlefield, then shuffle." +1: Draw a card
Black cards often feature characters from CP9 or the Dressrosa Saga
You Are Unworthy of Mercy You Cannot Hide from Me You Exist Only to Amuse You Live Only Because I Will It Your Fate Is Thrice Sealed Your Inescapable Doom Your Mistake Is My Triumph Your Nightmares Are Delicious Your Own Face Mocks You Your Plans Mean Nothing Your Puny Minds Cannot Fathom Your Will Is Not Your Own You Will Know True Suffering Best Scheme Cards As a casual variant, the concept of best scheme cards is very relative, but heres a few schemes that are really scary when the Archenemy player reveals them
An escalating army of Tarmogoyfs is hard to argue with