The Forest Is Angry event introduces hard mode to 99 Nights in the Forest and changes how the entire game is played. Corruption spreads across the map, rifts appear nightly, and failing to control them leads to permanent debuffs that make survival increasingly difficult. This guide explains exactly how the event works and how to manage it from start to finish.
What Is The Forest Is Angry Event?
The Forest Is Angry event is an optional hard mode that players can activate early in a run. Once enabled, the forest begins fighting back. Corruption spreads through rifts, trees, and wildlife, forcing players to actively manage the environment instead of only focusing on base defense and enemy waves.
Warning
Hard mode cannot be disabled once activated. Make sure your team is prepared before pulling the lever.
How to Activate Hard Mode in 99 Nights in the Forest
Step 1: Locate the Research Outpost
To start the event, players must visit the Research Outpost before night 3. This structure appears on the map once a map is crafted.
Step 2: Enter the Basement
Inside the Research Outpost is a basement containing notes and levers. Each player must pull their own lever to vote for hard mode.
Step 3: Pull the Hard Mode Lever
When all levers are activated, a short cutscene plays and the corruption system begins immediately.
Research Outpost location
Understanding the Corruption System
Corruption is the main mechanic of The Forest Is Angry event. It spreads over time through rifts and infected objects. The higher the corruption percentage, the more severe the debuffs become.
Corruption can be monitored using the Research Monitor, a buildable object unlocked after activating hard mode. It shows the current corruption level, the number of active rifts, and which debuffs are currently active.
If corruption is left unchecked, the run becomes significantly harder and can eventually spiral out of control.
Corruption Debuffs Explained
As corruption increases, debuffs are applied permanently for the remainder of the run.
At lower levels, corruption has little impact. As it rises, the deer becomes hostile and constantly hunts players. Passive healing is eventually disabled, forcing players to rely entirely on bandages and med kits. At high corruption levels, food begins to rot rapidly, making resource management much harder. Cultist waves also become stronger and more frequent.
Managing corruption early prevents these debuffs from stacking too quickly.
What Are Rifts and How Do They Work?
Rifts are purple corruption sources that spawn around the forest after hard mode begins. They infect nearby terrain, trees, and animals.
Rifts continuously increase corruption until they are dealt with.
How to Clear Rifts
Chop down infected trees near the rift
Kill corrupted animals in the area
Fully clear the surrounding corruption
Once an area is cleared, the rift stops spreading corruption.
Important
New rifts spawn approximately every night. You're fighting a constant battle to keep corruption manageable.
Corrupted Trees and Animals
Corrupted trees are easy to identify by their dark appearance and infection growth. Cutting them down reduces corruption. Stronger axes make this process faster.
Corrupted animals are more aggressive than normal versions and usually appear near rifts. Killing them also helps slow corruption spread. Corrupted meat can drop, though it is not especially valuable compared to the risk involved.
Players should clear corrupted areas as soon as they are discovered.
Using the Ping System
The Forest Is Angry update adds a ping system to help with coordination. PC players can ping using Q, while mobile players can use the bell icon.
Pings are useful for marking rift locations, alerting teammates to danger, and coordinating movement across the map. This is especially important in hard mode, where teamwork greatly improves survival chances.
Survival Strategy for The Forest Is Angry Event
Early in hard mode, players should focus on building the Research Monitor, upgrading weapons, and stockpiling healing items. Clearing rifts as soon as they appear keeps corruption manageable.
As the run progresses, rifts appear more often and enemies become stronger. Teams should regularly patrol the map and avoid letting corruption climb too high. Base defenses become more important as cultist waves intensify.
In late stages, food management and healing efficiency are critical, especially once passive healing is disabled. Team coordination becomes the deciding factor in whether a run succeeds or fails.
Rewards and Progression in Hard Mode
Hard mode does not introduce unique items, but it does offer increased rewards for long runs.
Double diamond rewards at night 50
Double diamond rewards at night 99
This makes hard mode the most efficient way to farm diamonds, despite the difficulty increase.
The Forest Is Angry update changes how survival works in 99 Nights in the Forest. Instead of focusing only on enemy waves, players must actively manage corruption across the map. Clearing rifts, tracking corruption, and staying prepared are the keys to completing hard mode successfully.
Understanding the system makes the update manageable, even if it feels punishing at first. With proper preparation and consistent corruption control, hard mode can be completed and used as an efficient way to earn diamonds.
For players new to 99 Nights in the Forest, we recommend mastering normal mode first. Check out our beginner's guide to learn the fundamentals before tackling hard mode's corruption system.