Multiple endings are confirmed, but their total is not
Yes—Underkeep's developer has confirmed multiple endings connected to your decisions. That does not yet provide a complete ending count or a checklist for unlocking each one. The useful distinction in an Underkeep multiple endings guide is between the developer's full-game announcement and the specific mushroom choices documented in the demo.
In the May 30, 2026 official “Closer to the Depths” update, Rake in Grass says work has begun on the introduction and ending sequences and confirms that the game's endings depend on decisions made throughout the adventure. The update does not identify the full set of endings or their individual requirements.
It also says the mushroom quest from the demo has been included in the full game with alterations. That supports expecting the quest to return in some form, rather than assuming its demo route and consequences transfer unchanged.
Two demo choices show how a quest can branch
Demo-ending spoilers follow. The opening errand asks you to gather five mushrooms for a cook. During exploration, a humanoid mushroom identifies those caps as missing family members and asks you to return them, giving the collection a second possible recipient.
The narrated sources document these alternatives:
| Choice | Evidence from the demo sources |
|---|---|
| Return the mushrooms to the mushroom character | Splattercatgaming and Near Tragedy describe the reunion, a spore-filled sequence, and the party turning into mushroom people before the demo completion message. |
| Bring the mushrooms to the cook | Solo dungeoneer returns the collected five to the cook, receives the original quest reward, and concludes the demo recording. |
These examples make the branching choice concrete. They do not prove that the full game has exactly two endings, or that those two recipients correspond one-to-one with its final endings.
The Splattercatgaming narrated run is useful for the transformation branch, while solo dungeoneer's run documents the cook hand-in. These are attributed player sources rather than our own playtesting.
Do not assume a special choice is automatically the best one
The official May update also discusses additional encounter options and outcomes. The developer warns that special choices should not always be assumed to be the safest or correct answer. The demo's mushroom-family branch illustrates why a generous-looking decision can produce an unexpected result.
For a first run, read the dialogue and decide which outcome you want to explore instead of treating a unique option as a guaranteed upgrade. If your aim is the demo's transformation sequence, return all five mushrooms to the mushroom character rather than handing them to the cook first.
There is no supported universal “good ending” route in these materials. Neither a particular party setup nor a single mushroom choice has been shown to guarantee a named full-game ending. Those instructions would need evidence from the complete adventure.
Demo saves do not carry the choice into the full game
A developer reply about save compatibility explains that the demo is separate from the full game, uses different levels, and has incompatible save files. The developer notes that the full game also starts in a forest, but the mushroom character is not encountered as early.
Do not plan a full-game ending around importing your completed demo save. The official statements support two separate facts: the complete adventure will have decision-dependent endings, and the demo is not a compatible first chapter that transfers its saved choices directly into that adventure.
That leaves the demo as a useful taste of branching quests. A full ending guide would need to establish the actual decision chains, available endings, and relevant release version before presenting an exhaustive walkthrough.
FAQ
Does Underkeep have multiple endings?
The developer has confirmed multiple decision-dependent endings for the full game in the official May 30, 2026 update.
How many endings are there?
The cited announcement does not give an exact number. Two documented demo hand-in alternatives should not be used as the full game's ending count.
What is the mushroom transformation ending?
Narrated demo runs describe the party becoming mushroom people after returning all five collected mushrooms to the humanoid mushroom character.
Will my demo choice transfer to the full game?
The developer says demo and full-game saves are incompatible and the levels differ. The mushroom quest also returns in an altered form, so its demo route should not be treated as unchanged release progression.