This can ultimately allow the player to potentially find a vital card that's necessary to win the game, whether through reducing the opponent's deck size, healing their Pokmon's health, or in Charizard's case, finding more Leon cards to discard to increase the damage output from Royal Blaze
And you can hold as many cards as you want in your hand
This has been realized expertly on cards such as Vault 11: Voters Dilemma
Underdog Underdog was specifically made for players who absolutely hate it when their opponent negates their card effects with monsters like Apollousa, Bow of the Goddess
My first thought was of the ancient carving of Mew shown in Mewtwo Strikes Back, which was created by the native people living in the Amazon jungle to honor their protector god and enshrine its eyelash
Eye of Nidhogg Transforms creatures into a dragon