Choose Portal
Choose Portal if you want the Includes Source SDK, Subtitle Options, and Camera Comfort side of the pairing. On Steam, it's Steam Deck Verified, so handheld play works out of the box. 81,472 Steam reviews back the pick.
Portal vs Mayhem in Single Valley
Portal and Mayhem in Single Valley both land in Action on Steam, which is why they keep getting compared. The comparison below is built from each game's Steam metadata — release year, genres, categories, Steam Deck status, price, and review score — refreshed daily by imho.run's scraper. Headline differences: Both are Action games on Steam. Portal (2007) is 14 years older than Mayhem in Single Valley (2021). Portal scores higher on Steam reviews (98.7% positive) than Mayhem in Single Valley (75.9% positive). No login or purchase needed — scroll for the full table, the verdict FAQ, and links to ranked similar games for both titles.
Which should you pick?
Choose Mayhem in Single Valley
Choose Mayhem in Single Valley if you want an Indie and Adventure experience. On Steam, it's currently about 70% cheaper on the Steam Store. Mayhem in Single Valley launched in 2021.
Both Portal and Mayhem in Single Valley sit in Action on Steam, so either pick lands in the same broad neighborhood. Use the side-by-side table for the feature view, or follow the "Games like" links below to see ranked alternatives for either title.
Side-by-side comparison
 Portal |  Mayhem in Single Valley | |
|---|---|---|
| Released | 2007 | 2021 |
| Genres | Action | Action, Indie, Adventure |
| Platforms | Windows, Linux | Windows |
| Steam Deck | Deck Verified | Deck Playable |
| Price | 9.99 USD | 2.99 USD |
| Steam reviews | 98.7% positive (81,472 reviews) | 75.9% positive (58 reviews) |
| Multiplayer | Single-player only | Single-player only |
| Developers | Valve | Fluxscopic Ltd. |
Side by side
- Both are Action games on Steam.
- Portal (2007) is 14 years older than Mayhem in Single Valley (2021).
- Portal scores higher on Steam reviews (98.7% positive) than Mayhem in Single Valley (75.9% positive).
- Mayhem in Single Valley is currently ~70% cheaper on Steam than Portal (2.99 USD vs. 9.99 USD).
- Steam Deck: Portal is Deck Verified, Mayhem in Single Valley is Deck Playable.
Portal vs Mayhem in Single Valley — FAQ
- Should I play Portal or Mayhem in Single Valley first?
- If you want chronology, Portal (2007) came out before Mayhem in Single Valley (2021). If neither is a sequel to the other, order doesn't really matter — start with whichever fits your current mood, since both share enough on Steam to make either a reasonable opener.
- Are Portal and Mayhem in Single Valley similar?
- They overlap on Action on Steam, so the catalogue groups them together — but "similar" depends on the specific mechanics. Use the genre + category rows above to decide whether the overlap matches what drew you to the one you've already played.