How to play
You fly a small space fighter that never stops moving forward. Waves of wireframe drone fighters come at you from every direction: turn toward them, put the crosshair on a drone and fire your twin lasers. Drones line up on you, fire glowing orange bolts and break away to come around again. A bolt flies straight, so a hard turn takes you out of its path; you can also shoot it down.
The blue shield takes hits first and recharges a few seconds after the last hit. When it is empty, hits damage the hull, which does not recharge during a wave. Each cleared wave fills the shield and repairs part of the hull. The run ends when the hull reaches zero.
Every fourth wave brings a carrier drone that fires from four glowing weak points and launches small darts. Shoot out the weak points first: that opens the shielded core, which shows on its top and underside, and destroying the core destroys the carrier and its escorts.
The difficulty sets how fast, how often and how accurately drones shoot, how many attack at once and how fast your shield recharges. On Easy a drone only fires while it is on your screen. On Normal and Hard a drone behind you can fire too, but only after a lock warning (a red arrow at the screen edge and a beep) that lasts 1.6 seconds on Normal and 1 second on Hard. Each wave is a little harder than the last, and the best score for each difficulty is kept in this browser.
Controls
- Mouse: the crosshair follows the pointer and the view turns toward it. The further it is from the centre, the faster you turn; inside the small ring in the middle you fly straight. Click or hold the left button to fire.
- Keyboard: ← → or A D turn, ↑ ↓ or W S raise and lower the nose, Space fires. A tap turns a little, holding turns faster, and the turn stops as soon as you let go.
- Touch: drag anywhere on the view and a stick appears under your finger. Hold the round FIRE button, or switch on AUTO, which fires whenever a target is under the crosshair.
- P or Esc pauses, F switches full screen, M switches the sound. Settings has the steering speed and an option to invert up and down.
How it works
Drawing 3D with lines
Every ship is a set of corner points joined by edges. For a point at offset d from your eye, the game measures d along the camera’s right, up and forward directions r, u and f and divides by the forward distance, so far things look small:
screen position = (cx + F·x/z, cy − F·y/z), F = (H/2) / tan 31°
So a view 1.04 to 1.98 times as wide as tall shows 62° from top to bottom; a wider view is capped at 100° across and a narrower one, as on an upright phone, is 64° across. An edge that passes behind you is cut just in front of the eye, so it never flips across the screen.
Leading a moving target
Lasers fly at 900 units per second plus your own speed of 42. For the target nearest the crosshair the game solves |D + v t| = s t, where D is the offset to the target, v its velocity relative to you and s the laser speed, and draws the answer as a small diamond, the lead marker. When the crosshair is within a few degrees of it (4.5° on Easy, 3.2° on Normal, 2.2° on Hard, 1.6 times more with keys or touch), the shot goes to the marker.
Heat and radar
Each shot adds 7 units of heat. The guns cool by 15 per second while firing and by 38 per second after a quarter of a second without shooting; at 100 they lock until the heat falls to 30. The arc around the crosshair shows the heat.
On the radar the centre is straight ahead, the dashed ring is directly to your sides and the outer edge is straight behind. The direction of a dot from the centre is the way to turn; filled dots are in front of you, hollow ones behind.
Things to try
- Fly at a drone head-on, fire a short burst, then turn hard before its bolt arrives.
- Track a target inside the centre ring: you fly straight and the lead marker stays still.
- Shoot down an incoming bolt to save your shield.
- The carrier slowly rolls: shoot the weak points facing you, the others come around.
- Try Auto-fire with the keyboard: you only steer, and the guns fire when a target is lined up.
Frequently asked questions
Why does my fighter keep turning?
The view turns while the crosshair is away from the centre. Move it back into the small ring to fly straight.
Can drones shoot me from behind?
On Easy, no. On Normal and Hard, only after the lock warning, so there is time to turn toward the arrow.
What do the arrows at the edge of the screen mean?
Each arrow points to a drone that is off screen. A red pulsing arrow is a lock warning, an orange one an incoming bolt, a large pink one the carrier.