Thought Shucker is a common Creature — Rat Rogue card from Bloomburrow (BLB), collector number 77. Current market price: $0.11 (foil $0.21), TCGplayer market prices via Scryfall.
Threshold — {1}{U}: Put a +1/+1 counter on this creature and draw a card. Activate only if there are seven or more cards in your graveyard and only once.