Choose Solarium
Choose Solarium if you want a Free To Play experience. On Steam, it's free to play, so the barrier to trying it is zero. Solarium launched in 2017.
Solarium vs PlanetMars3D: Spirit Mission
Solarium and PlanetMars3D: Spirit Mission both land in Adventure, Simulation 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 share Adventure, Simulation on Steam. Solarium (2017) is 9 years older than PlanetMars3D: Spirit Mission (2026). Solarium is free; PlanetMars3D: Spirit Mission is paid (Price unknown). 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 PlanetMars3D: Spirit Mission
Choose PlanetMars3D: Spirit Mission if you want an Indie and Casual game with Playable without Timed Input. On Steam, it's the newer release (2026) and ships with the modern feature baseline. PlanetMars3D: Spirit Mission launched in 2026.
Both Solarium and PlanetMars3D: Spirit Mission sit in Adventure and Simulation 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
 Solarium |  PlanetMars3D: Spirit Mission | |
|---|---|---|
| Released | 2017 | 2026 |
| Genres | Adventure, Simulation, Free To Play | Indie, Adventure, Simulation, Casual |
| Platforms | Windows | Windows, macOS |
| Steam Deck | Deck Playable | Unrated |
| Price | Free to play | Price unknown |
| Steam reviews | 72.2% positive (79 reviews) | — |
| Multiplayer | Single-player only | Single-player only |
| Developers | Sunfleck Software | 4AI Limited |
Side by side
- Both share Adventure, Simulation on Steam.
- Solarium (2017) is 9 years older than PlanetMars3D: Spirit Mission (2026).
- Solarium is free; PlanetMars3D: Spirit Mission is paid (Price unknown).
- Solarium is Deck Playable on Steam Deck; PlanetMars3D: Spirit Mission has no Deck rating yet.
Solarium vs PlanetMars3D: Spirit Mission — FAQ
- Should I play Solarium or PlanetMars3D: Spirit Mission first?
- If you want chronology, Solarium (2017) came out before PlanetMars3D: Spirit Mission (2026). 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 Solarium and PlanetMars3D: Spirit Mission similar?
- They overlap on Adventure, Simulation 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.
- Is Solarium free?
- Yes — Solarium is a free-to-play Steam title. PlanetMars3D: Spirit Mission is paid (Price unknown).
- Does Solarium run on Steam Deck?
- Yes — Solarium is rated Deck Playable by Valve. PlanetMars3D: Spirit Mission doesn't have a Deck rating yet, so its Deck behaviour is currently unverified.