Topography Tracker is a rare Creature — Merfolk Scout card from The Lost Caverns of Ixalan Commander (LCC), collector number 63. Current market price: $0.45, TCGplayer market prices via Scryfall.
When this creature enters, create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this token: Target creature you control explores. Activate only as a sorcery.") If a creature you control would explore, instead it explores, then it explores again.