Bioessence Hydra is a rare Creature — Hydra Mutant card from War of the Spark (WAR), collector number 186. Current market price: $0.28 (foil $0.39), TCGplayer market prices via Scryfall.
Trample This creature enters with a +1/+1 counter on it for each loyalty counter on planeswalkers you control. Whenever one or more loyalty counters are put on planeswalkers you control, put that many +1/+1 counters on this creature.