Enduring Sliver is a common Creature — Sliver card from Modern Horizons (MH1), collector number 6. Current market price: $0.19 (foil $0.57), TCGplayer market prices via Scryfall.
Outlast {2} ({2}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.) Other Sliver creatures you control have outlast {2}.