Rapid Run

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 browser-playable top-down 2D river-racing game titled “Rapid Run,” using a simple colorful flat visual style. Use an orthographic camera looking straight down at a vertically scrolling river course; the camera follows the player as it moves downstream, keeping the boat near the upper/middle portion of the screen while new river scenery moves into view. Render the scene with flat colored shapes and no perspective shading: bright blue water, solid green banks with darker green narrow edge strips, pale blue animated current streaks, white pulsing rapids, brown rocks, brown striped logs, purple rotating whirlpools with pale spiral rings, yellow coins, pink/red flags, and a small red-and-yellow boat with white wake trails.

The playfield is a winding river approximately 205 world units long. The river center curves smoothly from side to side and its width varies, with green land/banks outside the water. Place the player at the upstream start and constantly carry it downstream toward a finish line. The player is a tiny red boat shaped like a pointed triangular hull, with a pale yellow rectangular deck/center and two translucent white wake pieces behind it. Allow horizontal steering with A/D or the left/right arrow keys. Apply responsive acceleration and damping so left/right input changes horizontal velocity and the boat visibly leans slightly while turning. Allow W/up-arrow to speed up downstream and S/down-arrow to slow down slightly, but always maintain downstream current motion. The current should gradually become somewhat faster farther down the river.

Build a fixed obstacle course along the river. Include brown rock hazards, horizontal/angled brown logs with darker stripe details, and purple whirlpool hazards with rotating pale rings. Distribute them downriver at varied lateral offsets so the player must steer around them. Contact with a rock, log, whirlpool, or green bank causes a crash, briefly makes the boat invulnerable/blink, and pushes it away or disrupts its motion; whirlpools also pull/turn the boat toward their center before the crash. The player can suffer at most 3 crashes; on the third, end the run. If held against a bank for roughly several seconds, also end the run as stuck.

Place collectible floating yellow coins and occasional red/pink flags down the course, generally toward alternating sides of the river. When collected, hide them and add 1 coin for a yellow coin or 2 coins for a flag; award 100 points per coin and 200 per flag. Make collectibles gently bob and rotate. Add animated current streaks that drift downstream and recycle ahead of the camera, and white rapid strips that pulse in opacity and width. At the bottom of the course, show a white finish line with alternating black-and-white checker squares. The player wins when it reaches the finish line before the timer expires.

Give each run a 90-second countdown timer. The HUD is an always-visible overlay with dark translucent rounded pills at the upper left and upper right: show “Crashes 0/3 · Coins 0 · Score 0” (updating values) and “Time 90.0” (counting down). Add a horizontal progress bar along the bottom, yellow-to-green, showing distance from start to finish. On desktop, hide mobile controls. On touch/mobile layouts, show four dark/yellow-styled buttons near the bottom: up, left, down, and right, arranged as a directional pad; holding them should mirror W/A/S/D. Prevent the controls from scrolling the page.

Before play, show a centered dark translucent rounded instruction panel titled “Rapid Run,” with text explaining steering downriver before time runs out, A/D or arrow keys to steer, W/S or up/down to adjust speed, and avoiding rocks, logs, whirlpools, and green banks while collecting coins. Include a prominent yellow “Start Run” button. When the player wins or loses, stop gameplay and show a centered result panel: for success, “Finished!” with the number of collectibles and crashes, plus the final score and a “Run Again” button; for failure, “Run Over” with the reason (timer expired, too many crashes, or stuck at the bank), distance/collectibles, final score, and a “Try Again” button. Keep the overall presentation clean, arcade-like, and readable over the river.