X Trench Run
Stellar Swarm
Stellar Swarm is a free browser game where you fly a neon starship and try to outlast endless waves of geometric enemies. You move, the ship fires on its own, and the real game is choosing which weapons and upgrades to stack as the screen fills up.
It belongs to the horde survival family, so a run is short and you die a lot at first. The pull is the part between deaths: crystals you earn carry over and make the next ship a little stronger.
What is Stellar Swarm?
It is a 2D action survival game. You pilot a single ship against swarms of enemies that keep spawning, and your job is to stay alive while your weapons clear space around you. You pick a starting weapon, then unlock and upgrade more through a branching skill tree as the run goes on. Some upgrade paths lead to evolved versions of a weapon that hit much harder. When a run ends, you spend the crystals you collected on permanent upgrades to your ship, so progress sticks even when the run does not.
How to play
You only steer. The ship handles its own shooting, which leaves you to focus on positioning and on the upgrade choices that pop up.
Desktop controls
- WASD or arrow keys to move the ship
- P to pause and open the menu
Mobile controls
The game runs on phones and tablets. Drag on the screen to steer the ship around the swarm. The upgrade prompts are tapped the same way you would click them on desktop.
Reading the swarm
Enemies come in waves and close in from the edges. Your weapons fire in fixed patterns, so where you point the ship decides what gets hit. Keep moving into open space and let the swarm chase you into your own fire. Standing still is how most early runs end.
Weapons and upgrades
Weapons are the core of a run. You start with one and earn more as you level up during the run.
The skill tree
Level-ups offer a choice of new weapons or upgrades to ones you already have, laid out as a branching tree. Each pick narrows what you can build next, so a run turns into a small set of decisions about whether to spread across many weapons or pour everything into one or two.
Evolutions
Push a weapon far enough down its path and it can evolve into a stronger version. Evolutions are the payoff for committing to a weapon instead of grabbing one of everything. A single evolved weapon often clears the screen better than three half-leveled ones.
Crystals and permanent upgrades
Crystals you collect during a run are spent between runs on permanent ship upgrades. These carry over to every future run, so even a bad run that ends fast still feeds the long game. This is what makes the early deaths worth sitting through.
Tips for surviving longer
- Keep moving. A circling path lets your auto-fire sweep the swarm while you stay out of reach.
- Commit to a weapon early so you can reach its evolution before the run gets hard.
- Grab a movement or survivability upgrade when offered, not just damage. A faster ship dodges waves a slow glass cannon cannot.
- Spend crystals after every run. Banking them does nothing, and the next run is easier with the upgrade live.
- Watch for the moment the swarm density spikes and reposition before you get boxed into a corner.
What makes it work
The hook is that a single run is short but every run leaves you a bit stronger, so quitting feels worse than starting one more. Steering is simple enough to pick up in seconds, while the weapon choices give each run a different shape. A 4.7 rating from over ten thousand players suggests that loop lands for most people.
Stellar Swarm on mobile
Stellar Swarm is a browser game and does not have its own app. It still plays on phones and tablets here using touch controls. If you want something similar to install, these games have mobile versions:
- Paperly: Paper Plane Adventure: Google Play
- Deadly Descent: Google Play
- Robo Runner: Google Play · App Store
- Space Waves: Google Play · App Store
- Jump Into The Plane: Google Play · App Store
Similar games
If you like Stellar Swarm, try these other free games on X Trench Run.