Channeler Initiate is a rare Creature — Human Druid card from Amonkhet (AKH), collector number 160. Current market price: $0.31 (foil $0.74), TCGplayer market prices via Scryfall.
When this creature enters, put three -1/-1 counters on target creature you control. {T}, Remove a -1/-1 counter from this creature: Add one mana of any color.