Quick answer
What to do first
Check the Anomaly mode first. In a normal colony with a dormant monolith, activate when you want to engage the expansion and have basic food, medical and response capacity. An Anomaly starting scenario can activate on its own; Ambient Horror is a different mode and does not follow the same monolith progression.
Choose for your situation
| Situation | Choice | Reason | Before acting |
|---|---|---|---|
| Normal colony, survival unstable | Prepare first | Activation adds a new set of problems to manage. | Secure food, care and a response plan. |
| Normal colony, ready for Anomaly | Activate deliberately | You choose when to engage the progression. | Expect new systems rather than a free reward. |
| Anomaly starting scenario | Prepare immediately | The start does not provide the same indefinite delay. | Read scenario conditions. |
| Ambient Horror | Use that mode’s rules | It is not the standard monolith progression. | Do not diagnose the missing progression as a broken save. |
Check your Anomaly mode
Start by reading the scenario and storyteller settings. Anomaly can be present without every colony using the same progression path. Advice written for a normal dormant monolith does not automatically apply to the expansion’s special start.
Choose activate now or prepare first
For a normal colony, use readiness rather than a fixed day number. Can the colony keep eating during an interruption? Can it treat injuries and respond to a new threat? If not, postpone activation while stabilizing those systems.
Find a missing monolith
If the monolith is missing, confirm that Anomaly is enabled and that the selected mode expects one. Old saves and event-based opportunities can differ from a newly generated map. Look for the relevant in-game event or quest context rather than editing the save as a first response.
Set a spoiler boundary
This guide keeps later progression and endings unspoiled. Once you decide to engage, use the containment guide for the first holding setup and keep checking the information for each new entity. It does not promise that any preparation eliminates all risk.
Version & sources
Sources & what may change
- Applies to
- Core + Anomaly · PC 1.6.4850.
- Last verified
- 2026-09-04
- When to check again
- Recheck after a relevant game patch, DLC change or source correction. Mods can change these conditions.
Documentation reviewed; not an in-game test report. RimWorld Wiki is community-maintained, not Ludeon documentation.
Portions of the materials used to create this content/mod are trademarks and/or copyrighted works of Ludeon Studios Inc. All rights reserved by Ludeon. This content/mod is not official and is not endorsed by Ludeon.