Infestation

Infestations are a random event in Rimworld.

Spawning

During this event, insect hives spawn in an area below an Overhead Mountain. Soon, insects will pop out of these hives to defend their hive, and will aggressively chase down any perceived threats such as your colonists.

If the hives are kept well, they will reproduce, spawning more hives and insects. If all insects are killed, the hives will slowly die out after a while.

Strategy

Infestations are most threatening in mountain bases, as they can spawn practically anywhere inside your base. They are much less harmful in other bases though, and can be considered as a normal-level threat.

Products

Hives bring glow pods that glow for 20 days (as long as they’re installed) and can be reinstalled, or sold for a paltry price.
Hives also produce insect Jelly in stacks of 20 every day or so, so if you could trap the hives via walls and doors, you could potentially farm the insect Jelly, though the insects are liable to digging out, and can threaten your colonists when they try to retrieve the insect jelly.