Tap a star. Build a galaxy. Clickstellar is a cozy sci-fi idle clicker about the biggest number of all: a star's output. Tap a lone world to harvest Energy by hand, then let an ever-growing empire of reactors and megastructures pour it out for you even while the game is closed. Every tap is a spark. Land a critical SURGE , chain combos, and watch your Energy per second climb from a trickle to an astronomical torrent. Spend Energy on a deep tier of structures: Solar Collectors, Fusion Reactors, Antimatter Cores, Dyson Swarms, Nebula Extractors, Pulsar Arrays, Quasar Engines and beyond. Buy one at a time, in tens, MAX, or fill straight to the next ×25 milestone. Enhancements : dozens of one-time ×2 upgrades for your structures and taps. Synergies : structures that boost each other as your empire grows. Milestones : every 25 you own doubles that structure's output. Comets streak across the void, catch them for Frenzy multipliers, instant Windfalls, free structures, and rarer surprises. Blink and you'll miss them. When your world can give no more, collapse your entire empire into Dark Matter , a permanent boost to every future run. Each ascension reforges your planet into a brand-new star (cycling nine stellar types) beneath a shifting nebula sky. Spend Dark Matter on a sprawling prestige tree: sharper taps, cheaper structures, and full automation , an Auto-Harvester that taps for you and a Foreman that buys the best value on its own. Features A satisfying, always-climbing idle loop with real offline progress (bank up to 12 hours away). 60+ achievements, including hidden ones, each stacking a permanent production bonus. A ~40-node Dark Matter prestige tree with true idle automation. 7 comet event types, cross-structure synergies, and ×25 milestones. A living 3D centerpiece: a glowing planet that becomes a star with orbiting satellites and rings. Big-number notation (Short / Scientific / Engineering) for the truly ridiculous totals. Full controller support with on-screen prompts, great on the go. No ads, no timers, no nonsense. Just number, going up. Steam Deck & controller Play with a gamepad or the Deck's touch/trackpad, the whole game is navigable with a controller, with prompts that match whatever you're holding.
