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Project Eagle: A 3D Interactive Mars Base vs PlanetMars3D: Spirit Mission

Project Eagle: A 3D Interactive Mars Base and PlanetMars3D: Spirit Mission both land in 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 are Simulation games on Steam. Project Eagle: A 3D Interactive Mars Base (2018) is 8 years older than PlanetMars3D: Spirit Mission (2026). Project Eagle: A 3D Interactive Mars Base is free; PlanetMars3D: Spirit Mission is paid (3.99 USD). 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 Project Eagle: A 3D Interactive Mars Base

Choose Project Eagle: A 3D Interactive Mars Base if you want a Free To Play experience. On Steam, it's free to play, so the barrier to trying it is zero. Project Eagle: A 3D Interactive Mars Base launched in 2018.

Choose PlanetMars3D: Spirit Mission

Choose PlanetMars3D: Spirit Mission if you want an Indie, Adventure, and Casual game with Playable without Timed Input and #category_playable_at_your_own_pace. On Steam, it's the newer release (2026) and ships with the modern feature baseline. PlanetMars3D: Spirit Mission launched in 2026.

Both Project Eagle: A 3D Interactive Mars Base and PlanetMars3D: Spirit Mission sit in 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

Project Eagle: A 3D Interactive Mars Base vs PlanetMars3D: Spirit Mission — Steam metadata comparison
Project Eagle: A 3D Interactive Mars Base — Steam game coverProject Eagle: A 3D Interactive Mars BasePlanetMars3D: Spirit Mission — Steam game coverPlanetMars3D: Spirit Mission
Released20182026
GenresSimulation, Free To PlayIndie, Adventure, Simulation, Casual
PlatformsWindowsWindows, macOS
Steam DeckDeck PlayableUnrated
PriceFree to play3.99 USD
Steam reviews78.7% positive (367 reviews)—
MultiplayerSingle-player onlySingle-player only
DevelopersBlackbird Interactive4AI Limited

Side by side

Project Eagle: A 3D Interactive Mars Base vs PlanetMars3D: Spirit Mission — FAQ

Should I play Project Eagle: A 3D Interactive Mars Base or PlanetMars3D: Spirit Mission first?
If you want chronology, Project Eagle: A 3D Interactive Mars Base (2018) 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 Project Eagle: A 3D Interactive Mars Base and PlanetMars3D: Spirit Mission similar?
They overlap on 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 Project Eagle: A 3D Interactive Mars Base free?
Yes — Project Eagle: A 3D Interactive Mars Base is a free-to-play Steam title. PlanetMars3D: Spirit Mission is paid (3.99 USD).
Does Project Eagle: A 3D Interactive Mars Base run on Steam Deck?
Yes — Project Eagle: A 3D Interactive Mars Base is rated Deck Playable by Valve. PlanetMars3D: Spirit Mission doesn't have a Deck rating yet, so its Deck behaviour is currently unverified.
Project Eagle: A 3D Interactive Mars Base vs PlanetMars3D: Spirit Mission · imho.run