File: Cult.of.the.lamb.v1.0.17.incl.all.dlc.zip... [ Verified Source ]

Several "solid" guides for 100% completion highlight these specific steps for unique followers:

You can now bring the mushroom leader back to life. Following his questline to its end is required for certain "Regenerate" DLC trophies. 3. Cult Management & Efficiency File: Cult.of.the.Lamb.v1.0.17.Incl.ALL.DLC.zip...

The DLC and late-game updates add significant content after you defeat the final boss. Several "solid" guides for 100% completion highlight these