Graveyard Keeper 2 Bioreactor — Zombie Power & Factory Belt

Short answer

The Bioreactor is a factory machine that turns 5 Wheat → 1 Zombie Power on a powered conveyor. It does not need a zombie operator, but the belts do—budget Carousel power before you celebrate the recipe.

Unlock path

1. Research Wooden Kit II, then Bioreactor on the tech tree (130 red + 20 blue points).
2. Build at the factory desk: 10 Glass, 8 Bronze Gear, 6 Advanced Detail.
3. Queue the Zombie Power recipe on the machine once the build finishes.

If the option is greyed out, you are still missing Wooden Kit II or the factory district unlock—not a bug.

Belt setup that actually runs

Players search “bioreactor” because the machine has left input and right output only. A workable test loop:

1. Feed chest on the left belt with Wheat filtered as the only export toward the Bioreactor.
2. Output belt on the right into a receiving chest—leave it as the endpoint while testing.
3. Staff a Zombie Carousel (or enough carousel capacity) so the network has power; a miner elsewhere does not help this line.
4. Drop 5+ wheat, wait a cycle (~2½ minutes per unit at base timing), confirm Zombie Power lands in the output chest.

Misaligned belts (gap at the connector) are the usual reason “nothing happens.”

Why Zombie Power matters

• Assembly lines want it for appliance crates and Zombie Mechanisms tech.
• Magic Mirror / Bishop thread at the Royal Foundry asks for 3 Zombie Power (15 wheat at base yield)—tie this to Royal Foundry when you are ready.

When it stalls

Symptom	Likely fix
Machine idle, wheat in chest	Filter wrong, or belt not touching left port
Belts frozen	Carousel understaffed or total power below demand
“I researched it but can’t build”	Missing glass/gears/details stockpile

Related guides

• Factory & orders
• Factory setup
• Zombie power item
• Wheat & farming

Fan-made notes for Graveyard Keeper 2 — confirm costs, quest flags, and recipe yields on your save after patches.