Grand Warlord Radha is a rare Legendary Creature — Elf Warrior card from Dominaria (DOM), collector number 195. Current market price: $0.77 (foil $1.72), TCGplayer market prices via Scryfall.
Haste Whenever one or more creatures you control attack, add that much mana in any combination of {R} and/or {G}. Until end of turn, you don't lose this mana as steps and phases end.