Wizardry: Labyrinth of Lost Souls

Reveal 30% of the Dungeon of Trials. You should get this naturally since the Dungeon of Trials has 10 floors (the last 4 can only be accessed if you bought the DLC for 4,99$). Just map every tile you can and you should get the trophy on floor 3 or 4.

It will unlock after you mapped the last tile of the Trial Dungeon.