Silver Sable, Mercenary Leader is a uncommon Legendary Creature — Human Mercenary Hero card from Marvel's Spider-Man (SPM), collector number 13. Current market price: $0.26 (foil $0.33), TCGplayer market prices via Scryfall.
When Silver Sable enters, put a +1/+1 counter on another target creature. Whenever Silver Sable attacks, target modified creature you control gains lifelink until end of turn. (Equipment, Auras you control, and counters are modifications.)