The Mycelarium repeller mushroom is the unlock that handles the hedgehog. It was added in Demo 2.0 specifically to fight the animal that wanders across the forest floor and carries off the mushrooms you place on the surface, and players who have it report finally being able to control the hedgehog and get a steady food supply alongside the Predator Mushroom.
Mycelarium repeller mushroom: the anti-hedgehog unlock
Demo 2.0's announcement lists "Unlocked Repeller mushroom to fight that sneaky Hedgehog" alongside new visuals, a save system and a balance tweak. That is the whole job of the mushroom: it keeps the hedgehog off your surface mushrooms so the food you paid for stays where you put it.
The hedgehog is not the only animal the full game plans to add, so the Repeller is expected to cover more than one of them. The rest of the problem it solves is in how to stop hedgehogs eating mushrooms.
Repeller Charges and Repeller Regen Cost
The Repeller has two nodes of its own:
- Repeller Charges — how many times it can push the hedgehog back before it needs to recover.
- Repeller Regen Cost — what it costs to recharge those charges.
Both are bought with points, so a Repeller that is constantly busy with a hedgehog can be tuned rather than replaced.
Where the Repeller sits in the tree
In the upgrade tree the Repeller Mushroom sits under FRUITING BODIES, below the Spore Mushroom, with Repeller Charges and Repeller Regen Cost as its follow-up nodes. That placement matters for ordering: it is a child of the Spore Mushroom, so the Spore Mushroom has to be bought before it. The rest of the tree is in the upgrade tree guide.