Save and load games. Slots 0–2.
Stellarum is a risk-like game played in space. Terrain fog: each of your stars casts visibility based on its operational fleet only (dock ships do not extend range). An empty owned star lights only that star—no adjacent terrain—while links still stub outward into the unknown. With exactly 1 ship you see one hop and enemy/neutral fleet intel within that range; with 2–9 ships, two hops with intel; with 10 or more ships, three hops with intel. You always see your own fleets on stars you own. On neutral or enemy stars, fleet counts, fatigue, dock, pin markers, and berserker/awakened styling stay hidden until a scouting-capable star (one or more operational ships) includes that system in its visibility—terrain alone is not enough. Neutral enemy fleets will only attack if not threatened by an adjacent fleet of yours or if the fleet is too small. Beware the red enemies! They are Berserkers and will actively seek you out if they see you; pinning one in place takes a force equal to or larger than its own. At the end of a turn fleets are resupplied and rested and you gain new ships at your bases.
Capture 4 bases (besides your home) to win. You lose if you lose all your bases.
On a touch-first device you get extra on-screen controls; pinch-zoom still zooms the page for readability.
As fleets move they get fatigued, which is indicated by dots above the number of ships. Fatigue lowers combat effectiveness by 10% for each dot. The number in the center of each star is your operational fleet — the ships ready to move and fight.
When a fatigued fleet moves, some ships are disabled and need servicing. They travel with the fleet to the destination star and arrive in its dock. The number of docked ships at a star is shown in the lower-left (in brown).
Ship losses are tracked in the lower left. Each line shows a single battle as your losses | enemy losses. Win (green) means you won the battle; Loss (red) means you lost. Movement causes no losses, so it is not shown here.
Most neutral stars (light blue) hold position rather than attack you if you have a strong enough fleet on an adjacent star. A small red dot in the lower-right of a neutral star marks it as pinned by your nearby force. Use pinning to neutralize garrisons that are too large to take in a single attack: park a force next to the neutral to lock it in place, then chip it down with separate attacks from another direction or wait a turn for fatigue to clear and try again. The force needed to pin a star depends on its type: an ordinary blue neutral needs only one-third of its strength, an awakened neutral needs half, and a berserker (red) needs an equal or larger force. These thresholds are fixed - they never escalate as your empire grows. A pinned aggressive star (berserker or awakened) is fully locked: it makes no attack and no move that turn - but it keeps its target and resumes its campaign the moment the pin lifts.
Awakened neutrals look like normal neutrals - light blue body - but are wrapped in a distinctive orange glow ring with a thicker dark-orange border. They are not a separate faction or a spawn; they are ordinary blue garrisons that have just been stirred up by a nearby berserker takeover. Whenever a red aggressive neutral successfully captures one of your stars, every armed neutral within 2 hops of that star flips to awakened. The effect lasts 2-3 turns (randomized per cell) and then they revert to blue on their own.
While awakened, a neutral behaves like a berserker: it attacks at the aggressive 1.5x ratio instead of the defensive 2x, actively seeks out your territory, and locks onto a high-value target (your bases, supply chokepoints, or weak frontier stars) for several turns using the same target-commitment logic as true berserkers. It can still be pinned, but takes more force than a blue neutral - an awakened star needs half its strength to lock down (a berserker needs an equal force). A sudden orange cluster on your border means a berserker just cracked a cell nearby - kill that berserker fast, because each additional berserker takeover can awaken a fresh ring of neighbors and snowball the pressure.
Fatigue compounds badly during attacks. Each fatigue dot is both a 10% combat penalty AND 5% of the moving group disabled. On a successful attack the disabled ships at least land in the captured star's dock; on a failed attack they are destroyed at the destination. Attacking at fatigue 3 or 4 means 15-20% of your force is at risk of being lost outright before the battle even begins, and the survivors fight at 30-40% lower odds. When you can, pin the target and let fatigue cool down (it resets at end of turn) before pressing an offensive.
Aggressive neutrals commit to a target: red (berserker) and awakened neutrals now lock onto a high-value player target - your bases first, then supply chokepoints, then weak frontier stars - and stick with that target for several turns. Pinning one freezes it in place for that turn without wiping its plan; once the pin lifts, it resumes the same campaign and routes around obstacles toward the same star. Plan your defense around the assumption that any aggressive neutral within ~5 hops of a base is heading there, and keep your chokepoints garrisoned.
Every base has its own fleet, repair dock, and fatigue - moving ships out of one base does not drain the others. At the end of each turn you receive 1 reinforcement per owned star, distributed round-robin across your bases in turn (skipping any base already at the 99 cap). Reinforcements stop when your kingdom-wide ship total would exceed the fleet cap below. If every base is full, the remainder is dropped, so don't let bases sit at the cap.
Merging fleets: Right-click a star to select its fleet. Then click an adjacent friendly star and your selected fleet moves in. If that star already has a fleet, the two merge automatically. To select a different adjacent friendly fleet without moving into it first, click empty map to clear selection, then right-click that star. Each star is capped at 99 operational ships; any overflow above the cap bounces back to the source.
Fleet cap: your total kingdom fleet (every operational ship plus docked ships on all your stars) is limited to 50 + 50 per owned base + 1 per three owned systems (whole systems only—count all stars you own, including bases). Example: 2 bases and 32 owned systems → 50 + 100 + 10 = 160 max. Reinforcements that would push you over this cap are not produced. Losing a base does not destroy ships you already have—it only lowers the cap and may freeze production until losses bring you under the new maximum.
Base-to-base teleport: select a base, then Shift-click another base's edge marker (the green numbered circle on the rim, or the capital triangle at the central star—green while you own Central, gold otherwise) to teleport that base's fleet directly there. The cost is the same as a normal friendly move: the moving group gains 1 fatigue, 5% per fatigue level arrives disabled (in the destination dock), and any overflow above the destination's 99 cap stays at the source. Plain (non-shift) clicks on a marker still just re-focus the view. In split mode you can shift-click another base's marker to teleport just the selected count.