How to Get Ending 4 — Waste of time.

Requirements

• Reach the normal final evaluation rather than using the keyword or stabbing route.
• Finish with Interest between 1 and 5 inclusive.

Step-by-step

1. Avoid fatal choices and do not use the keyword at the two-activity checkpoint.
2. Use mostly neutral choices so final Interest lands between 1 and 5.
3. If you picked up the knife, decline to use it at the final decision; otherwise simply reach the final Mrs conversation.
4. The final normal evaluator sends Interest 1-5 to Ending 4.

If you get a different ending

• Interest 0 gives Ending 5.
• Interest 6-7 gives Ending 6.
• Interest 8 only gives Ending 7 if you never read a paper and never picked up the knife.