Beastmaster Ascension is a rare Enchantment card from Bloomburrow Commander (BLC), collector number 118. Current market price: $7.21, TCGplayer market prices via Scryfall.
Whenever a creature you control attacks, you may put a quest counter on this enchantment. As long as this enchantment has seven or more quest counters on it, creatures you control get +5/+5.