fairy's gift original yugioh card of The Mystical Elf - Pharaoh's Servant Yugis World Card type Yu-Gi-Oh! Shif, Fairy of The

Sure, your opponent might have ten beasts in their green deck, but Callous Oppressor would still be able to steal their four goblins, three elves, and two other creatures that weren't beasts

Purestrains prepare the battlefield and Broodlords ensure they can keep doing that, until eventually you have Patriarchs to come and turn their enemy's strength against each other

The only way around this kind of thing is a clone like Spark Double, which can copy legendary creatures without issue because it removes the legendary typing when it copies something, or another way around the legend rule like Mirror Gallery or Sakashima of a Thousand Faces

Some players show up to these contests with decks stacked so only well-funded opponents stand a chance