The Forest Wakes Up update — live around June 13–14, 2026 — added two meaningful choices to the 99 Nights in the Forest lobby screen: Biome Selection and Hardcore (Hard) mode. Both options were hidden from players who have never made it far in the game, so understanding them before your first attempt is genuinely useful.
What Biome Selection Does
Normally each run generates the Forest as its primary biome plus one secondary biome drawn at random from Snow, Volcanic, and Jungle — each at roughly a one-in-three chance. Biome selection in the lobby lets you replace that random roll with a deliberate pick, so you always know which secondary biome will appear before you load in.
This matters because each secondary biome changes the run substantially:
- Snow Biome adds a freeze meter that drains while you are outside, plus biome-exclusive content — the Ice Sword, Arctic Fox, Polar Bear, Warm Clothing Cabin, Ice Temple, and Snow Towers.
- Volcanic Biome replaces most of the terrain with dark grey rock and scatters lava pools that deal damage over time and ignite players and enemies alike.
If you are chasing a specific badge, farming a biome-exclusive item, or simply want to avoid a biome that punishes your playstyle, selection lets you skip the randomness entirely. One practical note: when a brand-new biome first releases, the game temporarily forces a 100% spawn rate for it (the other biomes drop to 0%), then reverts to the even split after roughly a week — selection is what lets you override that default behavior at any other time.
Unlock requirement: both Biome Selection and Hardcore mode are locked behind 10 highest days. "Highest days" is your best survival record across all runs. New players see the default random experience until they reach that threshold.
How Hardcore (Hard) Mode Works
Hard mode is an optional ruleset layered on top of a normal run. Activating it overlays spreading corruption across the map and spawns new rifts roughly every night, turning the run into a race against escalating pressure rather than a steady resource loop.
Corruption comes in four debuff types, and a long-running hard-mode save can have around three active at once:
- Passive healing is disabled at roughly 25% corruption.
- Cultist raids intensify at roughly 50% corruption — more cultists, higher-level cultists, attacking earlier in the run.
- Food Rot Spores activate at roughly 75% corruption, making stored food inedible.
- Hungry Deer: the deer gains aggro, deals more damage, and actively hunts players at night.
(These threshold percentages come from the 99-nights-in-the-forest.com wiki and are still being confirmed by the wider community, so treat the exact numbers as approximate.)
Important: Hard mode is permanent and one-way. Once you activate it for a run, you cannot switch it off. In-run activation happens at the Research Station or Research Outpost basement — each player must flip their own lever, and all levers must be flipped by the end of Day 2 or Hard mode cannot start for that run.
Whether the new lobby pre-selection replaces the in-run lever step entirely is not yet clearly documented. The safest assumption is that the lever activation in the Research Station still applies once you are in-game.
The Rewards — Why Bother?
Hard mode roughly doubles the late-game diamond payouts. Passing the Day 50 milestone gives 4 diamonds instead of the normal 2, and surviving all 99 nights gives 8 diamonds instead of 3. For players grinding diamonds to unlock classes or other content, a successful hard-mode run is far more efficient than replaying normal mode.
Hard mode is also the only way to unlock the rarest badge in the game — awarded for completing 99 nights on Hard — making it the required route for completionists chasing 100% badge coverage.
The Forest Wakes Up update also added 8 new badges (Toolfinding, Mastery, Carnivory, Free Throwing, Apprenticeship, Hoarding, Homemaking, Dream Team) and 7 new structures including the Sawmill, Cultist Ritual Circle, Cultist Tree, a new Large House, Stone Tower, Oil Pipes, and Ravine Bridge — so there is plenty of new content to find regardless of which mode you pick.
Which Should You Pick?
You are new or below 10 highest days: neither option is available yet. Focus on surviving past night 10, learning the resource loop and entity behaviors, and experimenting with the Forest biome before worrying about anything else.
You want relaxed progression: play normal mode and let the biome randomize, or use selection to pick Forest-only if you want the most familiar terrain. Save hard mode for later.
You want to farm a specific item or badge: use Biome Selection to guarantee the biome that drops it. This is the single biggest quality-of-life improvement in the update for mid-game players.
You want maximum diamonds or the exclusive badge: commit to Hard mode, flip the Research Station levers on Day 2, and be prepared to lose passive healing early and face intensifying raids. Go in with strong food stores, upgraded gear, and ideally a co-op partner — the Dream Team badge rewards co-op play specifically.
