Alacrian Jaguar is a common Creature — Cat Mount card from Aetherdrift (DFT), collector number 152. Current market price: $0.17 (foil $0.24), TCGplayer market prices via Scryfall.
Vigilance Whenever this creature attacks while saddled, it gets +2/+2 until end of turn. Saddle 1 (Tap any number of other creatures you control with total power 1 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)