Carry the pickaxe, then left-click the rubble
You do not need to equip the pickaxe to clear Underkeep's demo rock piles. The reported solution is to keep the tool in your inventory and left-click the blocking pile of rocks. That distinction solves the problem behind many searches for Underkeep how to use pickaxe: swinging a weapon at the blockage is not the same interaction.
The detailed directions come from players in the Steam discussion about the demo's mushroom route. One player explains that attacking the rockslide with weapons did not work; another describes trying to use the pickaxe on the wall and right-clicking before discovering the left-click solution. Edelweiss's route then explicitly pairs carrying the pickaxe with left-clicking the rock pile.
These are attributed demo reports. They provide a practical solution for that particular obstruction without claiming that the tool opens every wall or obstacle in the full game.
Find the tool in the mushroom character's chamber
The community route places the pickaxe in the chamber containing the humanoid mushroom. Search that room for the tool and collect it before returning to the blockage. Narrated demo runs by Nookrium and Near Tragedy also identify a digging tool around the mushroom character's area and connect it with getting past the blocked route.
For the mushroom objective, the reported rock pile is south of the area where you meet the first purple worm. The complete sequence is:
- Explore until you reach the humanoid mushroom's chamber.
- Collect the pickaxe and check that it is in your inventory.
- Return to the rock pile blocking the passage south of the first purple worm area.
- Left-click the rock pile while carrying the tool.
- Continue through the newly accessible route and inspect the area for the mushroom.
The official demo page describes one dungeon and a limited starting area. These directions apply to that demo route, rather than a confirmed full-game map.
Check the interaction before trying another weapon
If you have the pickaxe but nothing seems to happen, start with what you are clicking. The player reports refer to the rock pile, not dragging the pickaxe onto a character, equipping it in a weapon slot, or attacking a nearby wall. Repeated attacks are especially misleading because the demo also teaches you to attack fragile crates.
Use the two situations differently:
- Crate or fragile container: the tutorial introduces breaking it with an attack, then checking the revealed items.
- Blocking rubble: carry the pickaxe and left-click the pile.
- Locked chest: investigate the required key; the pickaxe route does not establish that it can open locks.
Do not turn a cracked texture into a guaranteed tool target. The narrated sources contain guesses about other walls, but those guesses are not a verified list of places the pickaxe works. Solve the known rubble interaction first and let the actual response of another object determine whether it is relevant.
FAQ
Do I equip the pickaxe?
The reported demo solution does not require equipping it. Keep it in inventory and left-click the blocking rock pile.
Where do I find it?
The player route places it in the chamber where you meet the humanoid mushroom character. Check the room and collect the tool before returning to the rubble.
Why do weapon attacks not clear the rockslide?
Players describe that exact mistake. The rubble uses the carried-pickaxe interaction, which differs from attacking breakable crates.
Does this help me find the fifth mushroom?
Yes. The community's five-mushroom route places one beyond the rock pile south of the first purple worm area. Carry the pickaxe, clear the blockage, and search the newly accessible space.