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Squirrel's Pick Squirrel's PickThe best game on this page. If you only try one, try this.
Colony SimBase-BuildingSurvival
$24.99 ~166.9 hr median no co-op complexity: heavy 96.7% of 142k
The Squirrel's verdictOxygen Not Included suits players who want deep colony survival with full save and pause control at any time. It replaces insects with duplicants and swaps timed combat missions for thermodynamics, gas physics, and pipe management. Reviews warn the cheerful art hides serious systems complexity. Median playtime is 166.9 hours, and the 96.7% positive rating reflects a well-supported, complete release.
Not for you if you want the ant colony theme, narrated bug facts, or RTS combat missions rather than physics-driven colony engineering.
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Closest Match Closest MatchThe most similar game to the anchor, by what players say. Budget Pick Budget PickThe best game here for the least money.
City BuilderBase-BuildingGrand Strategy
$9.99 ~11.7 hr median no co-op complexity: light 87.9% of 1k
The Squirrel's verdictBuggos fits players who want insect-swarm combat in short, low-commitment sessions. It shares the bug-war premise and mission-based upgrade structure, but your swarm doesn't fully respond to direct control, making it an auto-battler rather than an RTS. At a median of 11.7 hours total, sessions are short by default. Reviews flag AOE-heavy difficulty spikes and DLC balance problems in later stages.
Not for you if you want hands-on colony micromanagement or a deep upgrade tree rather than an auto-battler where late-game difficulty reduces to AOE spam.
3
Colony SimAutomationProcedural Generation
Strong Mods Strong ModsA deep, active modding scene extends it past its base content.
$19.99 ~45.6 hr median no co-op complexity: heavy 87.3% of 953
The Squirrel's verdictBoth center on ant colonies, but Microtopia swaps missions and combat for factory automation: you route ants as workers through supply chains and manage their lifespan as a resource. Progression runs through a tech tree instead of mission-based upgrades. No combat, no narrator, median playtime 45.6 hours per Steam data.
Not for you if you want RTS combat and narrated missions rather than a logistics puzzle managing ant lifespans and repetitive manual building placement.
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Base BuildingColony SimCity Builder
$19.99 ~20 hr median no co-op complexity: light 83.8% of 642
The Squirrel's verdictBuggos 2 keeps the insect-colony premise and evolution-tree progression that Empires of the Undergrowth fans expect, but reviews describe it as a lighter auto-battler rather than a full RTS, with a thinner tech tree and a campaign several players call short at around 10-20 hours. Median playtime sits at 20 hours for $19.99.
Not for you if you want RTS-level tactical depth and a robust tech tree rather than a shorter auto-battler with reported balance and difficulty-crash issues.
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Colony SimCity BuilderPost-apocalyptic
$13.49 ~24.8 hr median no co-op complexity: light 79.4% of 1k
The Squirrel's verdictAfter Inc: Revival replaces ant colonies with zombie survival and breaks its missions into shorter discrete segments rather than the anchor's long uninterruptible runs. Reviews describe it as a mobile-style game with an energy mechanic that caps daily playtime, no endless mode, and no random scenarios once the campaign ends. Median playtime is 24.8 hours at $13.49.
Not for you if you want freeform replayability or extended sessions, since an energy system limits how much you can play in a given day.
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Space Colony: Steam Edition
PC
City BuilderImmersive SimColony Sim
$14.99 ~14.2 hr median no co-op complexity: moderate 80.1% of 663
The Squirrel's verdictSpace Colony shares the colony-management core: build structures, manage resource flows, keep your population functional under mission pressure. The difference is scale and focus — instead of ant swarms and time-pressured combat missions, you're micromanaging individual human colonists' needs (hygiene, social, sleep) like a sci-fi Sims. Median playtime runs 14.2 hours.
Not for you if you want swarm-scale strategy and combat rather than babysitting individual colonists' personal needs and conflicts.
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Sci-fiSurvivalColony Sim
$9.99 ~37.2 hr median no co-op complexity: moderate 78.5% of 316
The Squirrel's verdictMercury Fallen suits players drawn to open-ended underground colony building with research progression and the freedom to save and quick-load at will. Early hours are slow by reviewer accounts, and multiple reviews flag thin late-game balance once core research is unlocked, with no meaningful objective remaining. Median playtime is 37.2 hours at $9.99.
Not for you if you want mission-based combat tension or a late game with sustained challenge rather than freeform base-building that runs thin.
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Ant War: Domination
PCMacLinux
ClassicAdventureBase-Building
$4.99 ~4.3 hr median no co-op complexity: light 57.4% of 251
The Squirrel's verdictPlayers who want colony-building in brief, interruptible sessions will find Ant War: Domination fits that gap: it's a turn-based clicker where you pick ant types, buy upgrades, and resolve battles in sittings you can end whenever. Median playtime is 4.3 hours total. Reviews consistently describe it as repetitive, visually dated, and nearly identical to a free browser flash game from over a decade ago.
Not for you if you want real-time strategy, modern visuals, or combat that stays engaging beyond the first few minutes.