Happy Birthday Trap

The Happy Birthday trap is an advanced trap building with a large, ground-mounted contraption with a flexible spiked mesh of sticks that flips up from the ground and slams into enemies when tripped. They were added in update v0.01 of The Forest.

Gameplay
Happy Birthday traps instantly kill cannibals on all difficulties. On Normal difficulty, mutants also die in one hit, but on Hard and Hard Survival, they will require two. The Happy Birthday trap is most effective against Armsy and occasionally Virginia, but Cowman may run through too quickly for the trap to trigger.

Once sprung, it is solid and acts as a short barrier, which can block cannibals and mutants. If it is reset, they will be able to move through it again. Cannibals in front of the spikes when they are triggered will be impaled on them and held up. The trap only works effectively on one side, as cannibals can sprint through the trap and the spikes pop out behind them, so it doesn't do any damage.

The survival guide's blueprint for the Happy Birthday trap seems to be much smaller than the finished version: this is because it was increased in size in v0.19. It is also worth noting this may not have been the original name of the trap, as evidenced in the survival guide by a piece of tape replacing its original name with the new one.

As of v0.68, resetting traps now requires to hold the “Take” action for 3 seconds.

Happy birthday traps do the exact same amount of damage as deadfall traps.

Strengths & Weaknesses
+ More consistent than the deadfall trap. + Can't be destroyed by cannibals. + Serves as a solid barrier while triggered.

- Very small area of effect. - Very expensive compared to the deadfall trap, requiring precious rope. - Only works from one side.