The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- ?? characters (12 members)
- ? characters (1 member)
- Abilities (8 members)
- Actors (84 members)
- Actors images (13 members)
- Administrative tasks (4 members)
- Administrative templates (13 members)
- Administrators' noticeboard Forum (3 members)
- Advisory templates (8 members)
- Affiliations (16 members)
- Agent images (16 members)
- Agents (16 members)
- Agents in MxO (10 members)
- Animals (5 members)
- Appearance templates (1 member)
- Archives (10 members)
- Article management templates (1 member)
- Articles to be merged (0 members)
- Articles with an excess of redlinks (0 members)
- Ashencourt Construct Images (3 members)
- Attention required (2 members)
- Authors (1 member)
- Battles (13 members)
- BlogListingPage (1 member)
- Blog posts (80 members)
- Bluepills (74 members)
- Bluepills in MxO (12 members)
- Box art (13 members)
- Browse (3 members)
- CC-BY files (1 member)
- Candidates for deletion (7 members)
- Cast (4 members)
- Character images (47 members)
- Character stubs (407 members)
- Characters (7 members)
- Characters by Affiliation (0 members)
- Characters by Species (0 members)
- Characters by affiliation (4 members)
- Characters by appearance (9 members)
- Characters by gender (2 members)
- Characters by organization (6 members)
- Characters by position (5 members)
- Characters by species (3 members)
- Characters in A Detective Story (2 members)
- Characters in A Life Less Empty (5 members)
- Characters in A Path Among Stones (8 members)
- Characters in A Sword of a Different Color (5 members)
- Characters in An Asset to the System (4 members)
- Characters in An Easy One (1 member)
- Characters in Artistic Freedom (3 members)