Simian Sling is a common Artifact Creature — Equipment Monkey card from Kamigawa: Neon Dynasty (NEO), collector number 163. Current market price: $0.23 (foil $0.38), TCGplayer market prices via Scryfall.
Equipped creature gets +1/+1. Whenever this creature or equipped creature becomes blocked, it deals 1 damage to defending player. Reconfigure {2} ({2}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)