MOLD-09

MOLD-09 is a dark action roguelite about surviving an endless apartment block. Behind its doors lie hordes, traps, discarded junk, and the parts for your next weapon. Clear apartments, survive arena waves, and open the way to the elevator. Make the climb alone or bring up to three friends in online co-op.

The official designation is MOLD-09: Mycelial Organism Lethal Degeneration, strain 09. The residents just call it the Mold.

Build a weapon that follows your rules

A frame, physical parts, and modules determine how your weapon behaves. Change the attack sequence, add ricochets and homing, or make a hit trigger another shot. Balance energy use and recharge time: a clever combination still needs to fire when you need it.

Pick up weapons dropped by enemies, rebuild them at the workbench, and scrap unwanted gear for Rust. One new part can change the direction of your entire build.

Explore every floor

Layouts, encounters, and rewards change between runs. Choose which rooms to tackle first, take on errands for the residents, and decide how to spend your Rust at the merchant. Apartments and arenas demand different approaches: hold a doorway, dodge a trap, or find a way out before the crowd surrounds you.

When the emergency begins

Some floors have a danger that interrupts the fighting. A warning gives you time to reach the elevator or find a sealed shelter locker. Staying outside can be fatal. In co-op, the shelter is shared, but everyone has to make it inside.

Share the building

Play solo or team up through Steam. Explore ordinary rooms separately, assemble your own weapons, and choose your own rewards. Regroup at the large arena and the elevator to move on together. One player's menu or workbench does not pause the run for everyone else.

Keep what you learned

Try another build, choose different upgrades, and develop permanent improvements through Dispatch. The Rust collected during a run is lost when you die; the permanent upgrades you have already unlocked remain. Your next attempt starts with another choice: what to bring, and how far to climb.