The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Templates (22 members)
- Terminal Reality (Developer) (3 members)
- Terrible Posture Games (Developer) (1 member)
- Test Drive (Series) (2 members)
- Teyon (Developer) (4 members)
- Thatgamecompany (Developer) (6 members)
- The Adventure Company (Developer) (1 member)
- The Adventure Company (Publisher) (1 member)
- The Bearded Ladies Consulting (Developer) (1 member)
- The Behemoth (Developer) (1 member)
- The Bigs (Series) (2 members)
- The Darkness (Series) (2 members)
- The Elder Scrolls (Series) (2 members)
- The Farm 51 (Developer) (2 members)
- The Fyzz Facility (Publisher) (1 member)
- The Godfather (Series) (1 member)
- The House of the Dead (Series) (3 members)
- The Idolmaster (Series) (5 members)
- The King of Fighters (Series) (5 members)
- The Legend of Heroes (Series) (6 members)
- The Lord of the Rings (Series) (1 member)
- The Muteki Corporation (Developer) (2 members)
- The Muteki Corporation (Publisher) (2 members)
- The Odd Gentlemen (Developer) (1 member)
- The Price is Right (Series) (2 members)
- The Quantum Astrophysicists Guild (Developer) (1 member)
- The Quantum Astrophysicists Guild (Publisher) (1 member)
- The Simpsons (Series) (1 member)
- The Sims (Series) (3 members)
- The Voice (Series) (1 member)
- The Walking Dead (Series) (4 members)
- The Workshop (Developer) (1 member)
- Third-person shooter (Genre) (78 members)
- TickTock Games (Developer) (1 member)
- Tiger Hill Entertainment (Developer) (1 member)
- Tigon Studios (Developer) (2 members)
- TikGames (Developer) (4 members)
- TikGames (Publisher) (5 members)
- Tiki Games (Developer) (1 member)
- Tiki Games (Publisher) (1 member)
- TimeGate Studios (Developer) (2 members)
- TimeGate Studios (Publisher) (2 members)
- Time Crisis (Series) (2 members)
- Timeline Interactive (Developer) (1 member)
- Titan Studios (Developer) (1 member)
- ToeJam and Earl (Series) (2 members)
- Tom Clancy's Ghost Recon (Series) (2 members)
- Tom Clancy's H.A.W.X (Series) (2 members)
- Tom Clancy's Rainbow Six (Series) (1 member)
- Tom Clancy's Splinter Cell (Series) (3 members)