Thallid Shell-Dweller is a common Creature — Fungus card from Modern Masters (MMA), collector number 169. Current market price: $0.30 (foil $0.63), TCGplayer market prices via Scryfall.
Defender At the beginning of your upkeep, put a spore counter on this creature. Remove three spore counters from this creature: Create a 1/1 green Saproling creature token.