Jennika, Bad Apple Big Sister is a common Legendary Creature — Mutant Ninja Turtle card from Teenage Mutant Ninja Turtles (TMT), collector number 10. Current market price: $0.13 (foil $0.20), TCGplayer market prices via Scryfall.
When Jennika enters, create a 2/2 red Mutant creature token. Plainscycling {2} ({2}, Discard this card: Search your library for a Plains card, reveal it, put it into your hand, then shuffle.)