Star Surge

Cinevva's analyzer read this game's design doc and its source, then wrote the brief below. "Make your own" hands it to the game creator as your opening message, so you start from a real spec rather than a one-line idea.

Create a responsive full-screen 2D vertical arcade space shooter titled “Star Surge,” rendered on an HTML canvas with a dark, polished neon sci-fi presentation. The playfield fills the viewport with no scrolling camera: use a nearly black/navy vertical gradient background (#040816 at the top, #07152a mid-screen, #02050c at the bottom), a subtle blue radial glow centered around the lower-middle of the screen, and about 85 small pale stars moving downward at varied speeds; when a star exits the bottom, recycle it to the top. Use a slight screen shake on impacts and explosions.

The player is a small blue-and-white pointed spaceship near the bottom of the screen, visually resembling a Kenney-style space shooter player ship, with a bright cyan animated engine flame. Keep the ship within the horizontal bounds and the lower 55% of the playfield (roughly y >= 45% of the viewport and at least 60 px from the bottom). On desktop, move with A/D or left/right arrows (the code also supports W/S and up/down for vertical movement); on touch/mobile, let the player drag the ship using pointer/touch input, smoothly following the pointer. Movement speed is about 420 px/sec. The ship fires automatically, with no fire button: the default Blaster fires one narrow glowing cyan vertical shot every 0.26 seconds upward.

Spawn enemies continuously from above the top edge. The spawn interval starts around 0.95 seconds and decreases by 0.07 seconds per wave, never below 0.26 seconds. Waves advance every 18 seconds. Most enemies are colorful small fighter ships, randomly selected blue, green, or red, entering from above with downward speeds around 90–130 px/sec plus 13 px/sec per wave. Fighters drift horizontally and sway slightly, bounce when reaching side bounds, and periodically fire a glowing pink/red round enemy projectile downward, initially after 0.9–1.8 seconds and then every 1.1–2.2 seconds while they are above the lower half. Fighter enemies normally have 1 hit point, with a chance of 2 HP after wave 4; show a small health bar above multi-hit enemies. Also spawn gray rotating meteors with irregular space-rock sprites, roughly 22–45% probability depending on wave, size 36–56 px, downward speed 110–170 plus 11 px/sec per wave, horizontal drift, rotation, and 2 HP. Enemies that pass below the screen disappear. Colliding with an enemy or enemy projectile costs one life unless a shield is active.

Player shots are bright cyan with a glow. The default Blaster fires one shot straight up at about 640 px/sec. When a player projectile hits an enemy, remove the shot, reduce HP, and create a small cyan particle burst. Destroying a normal fighter awards 12 points; destroying a meteor awards 20 points, creates a larger gold/orange explosion, and causes stronger screen shake. Use glowing square/rectangular particles for explosions and impact effects. When the player loses a life, create a larger pink/red burst and shake the screen. Start with 3 lives; when lives reach zero, stop the run and show the game-over overlay.

Destroyed enemies sometimes release collectible star-shaped power-ups that fall downward at roughly 95–125 px/sec. Release one whenever the destruction counter is divisible by 7, or with a 12% random chance otherwise. Collecting one activates its effect for 8 seconds and plays a power-up sound. The three power-up types are Spread Shot, Rapid Fire, and Shield. Spread Shot changes firing to three cyan shots per volley: one straight shot and two angled shots (about ±140 horizontal velocity, roughly 580 vertical velocity), at a 0.22-second interval. Rapid Fire fires two parallel shots at once at about 700 px/sec with a 0.12-second interval. When their timers expire, revert to the standard Blaster and 0.26-second interval. Shield creates a pulsing translucent aqua circular bubble around the ship for 8 seconds; while active, damage does not cost a life, instead shortening the remaining shield duration by about 1.4 seconds and producing a cyan burst. Power-up icons should be rotating blue or yellow star sprites; draw a small dark label box below each with the first letter of its type (S, R, or S, matching the implementation’s abbreviated label behavior).

Add a fixed HUD above the canvas using translucent dark glass panels with rounded corners, thin blue borders, blur/shadow styling, and light text. At top-left show “Score” with the current score, “Lives” with the current lives, and “Wave” with the current wave. At top-right show the current status: normally “BLASTER” in cyan and “Auto-fire online”; during a timed weapon power-up show “SPREAD SHOT” or “RAPID FIRE” with its remaining seconds; while shielded show “SHIELD” in aqua with “X.Xs shield active.” At the bottom-left show a rounded instruction panel: “Drag the ship to move. On desktop, use A D or arrows — shooting is automatic. Grab stars for spread shot, rapid fire, and shields.” Make the HUD responsive with safe-area padding and allow it to overlay the game without intercepting gameplay pointer input.

On initial load, show a centered modal overlay titled “Star Surge,” with the description “Arcade space shooter with auto-fire power-ups. Survive the wave, catch stars, and clear the screen.” and a prominent cyan gradient “Start run” button. Clicking it initializes score to 0, lives to 3, wave to 1, clears all entities/effects, places the ship at the center near 82% viewport height, and starts the run. When the player is defeated, replace the modal title with “Run over,” show text in the form “Score [value] — catch a better power-up chain and try again.” and change the button to “Restart run.” Include simple laser and power-up audio effects, unlocked after the first pointer or keyboard interaction. Use smooth animation with delta-time updates, responsive canvas resizing, crisp sprite rendering, neon glows, particle bursts, and the supplied Kenney-style assets: blue player ship, blue/green/red enemy fighters, gray meteor, and blue/yellow star power-up sprites.