Ever since the Fomori's attempt long ago to extinguish Chimil's light, the Oltec have taken extensive measures to never get lost in the Core.

The Lost Caverns of Ixalan

Cartographer's Companion

When Cartographer's Companion enters the battlefield, create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this artifact: Target creature you control explores. Activate only as a sorcery.")

When Cartographer's Companion enters, create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this artifact: Target creature you control explores. Activate only as a sorcery.")