Hangarback Walker is a rare Artifact Creature — Construct card from Commander Masters (CMM), collector number 951. Current market price: $0.52, TCGplayer market prices via Scryfall.
This creature enters with X +1/+1 counters on it. When this creature dies, create a 1/1 colorless Thopter artifact creature token with flying for each +1/+1 counter on this creature. {1}, {T}: Put a +1/+1 counter on this creature.