Mapping: The Trash-Tier Skill That Got Me Into a Top-Tier Party: Volume 2 by Udon Kamono

Note has managed to land himself a spot in a top-tier party, but even greater challenges await as his training ramps up. The Arrivers set foot in the dungeon for the first time in six months, and Note has to work twice as hard to keep up with everyone... Little does he know that will be the least of his worries after he and Erin get separated from the group. When they find themselves on an unexplored floor, Note will have to put his mettle to the test and use everything he’s learned to get them out alive.