Alpine Guide is a uncommon Snow Creature — Human Scout card from Modern Horizons (MH1), collector number 117. Current market price: $0.22 (foil $0.55), TCGplayer market prices via Scryfall.
When this creature enters, you may search your library for a Mountain card, put that card onto the battlefield tapped, then shuffle. This creature attacks each combat if able. When this creature leaves the battlefield, sacrifice a Mountain.