Emberline Defense

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 browser tower-defense game titled “Emberline Defense,” rendered with an HTML canvas filling the viewport and a fixed dark translucent HUD layered above it. Use a 960x620 logical game world scaled to the screen. The visual style is polished neon sci-fi: a deep navy-to-blue vertical gradient background with a subtle 40px blue grid, a thick rounded dark road winding from offscreen left to offscreen right, and a dashed blue-gray center line. The exact road route is a continuous polyline with rounded joins: start at (-30,180), travel to (150,180), down to (150,400), right to (360,400), up to (360,150), right to (650,150), down to (650,470), then right to (990,470). Draw the road as a very dark 68px under-stroke, a slate 58px main stroke, and a thin dashed center stripe. Enemies enter from a glowing purple circular portal near the left start of the road and travel along this route toward a glowing gold base/core at the right endpoint. If an enemy reaches the endpoint, remove it and reduce base health by 1; at zero health, end the game and show a restart option.

The player starts with 120 gold, base health 20, wave 0, and no towers. Place nine circular build pads away from the road at these logical coordinates: (80,90), (275,110), (520,90), (795,180), (90,300), (260,510), (500,520), (790,360), and (820,540). Empty pads are translucent blue circles about 25px radius with cyan outlines and a centered plus sign, visible/clickable only as build locations; occupied pads become subdued. Allow the player to tap/click an empty pad when no wave is active and spend 50 gold to build a Pulse Tower. Also provide a “Build Tower · 50” button that builds on the nearest empty pad. Towers are small glowing cyan circular turrets with a dark inner core, a light outline, and a gold level number. Tapping a tower selects it and displays a circular range indicator. A level-1 tower has 128 range, 12 damage, and a 0.72 second firing interval. Towers automatically target the furthest-along enemy within range and fire small bright cyan projectiles; on impact, subtract tower damage and emit white/cyan particles. Towers should have visible firing and hit particle bursts.

Implement ten sequential waves. The player presses “Start Wave 1” initially, then the button changes to start the next wave after each cleared wave. Wave N spawns 6 + N enemies, one at a time, initially with roughly 0.85 seconds between spawns (never below 0.32 seconds), and enemies move along the path at speed 34 + N*2.7. Each enemy is a glowing red circular creature around 13px radius with two dark eyes, a dark health-bar backing above it, and a green health bar; its health is 38 + N*18 and its kill reward is 8 + floor(N*1.5) gold. Towers kill enemies by reducing HP to zero, award the enemy’s gold, and create a gold particle burst. When all wave enemies have spawned and been destroyed, award an end-of-wave bonus of 30 + N*8 gold, stop the wave, and permit upgrades. Winning wave 10 displays “Victory! The ember road is safe.”, hides the wave control, and shows Restart. Losing displays “The base fell. Rebuild and try a stronger upgrade path.” and shows Restart.

Selected towers can be upgraded only between waves. Upgrade costs are 70 for level 1→2, 125 for level 2→3, and 180 for level 3→4. Each upgrade increases damage by 9, increases range by 18, and reduces fire interval by 0.12 seconds, clamped to a minimum interval of 0.28 seconds. Maximum level is 4. Show selected tower details such as “Pulse Tower · Level X · Y damage · Z range” and an upgrade button whose label includes the current cost; disable it during waves, at max level, or without sufficient gold. Do not allow building or upgrading during an active wave.

Add a speed control active only during waves. It cycles simulation speed from 1x to 2x to 4x and back to 1x, with the label cycling between “▶▶ 2x” and “▶▶ 4x” as in the reference implementation. Apply the multiplier to enemy movement, spawning, tower cooldowns, projectiles, and particles. Keep the game playable by pointer/touch input and prevent canvas scrolling.

Create the HUD as fixed, responsive dark glass panels. Across the top show four stat cards labeled BASE, GOLD, WAVE, and ENEMIES; show base health, current gold, current wave out of 10 (before starting, use “Start Wave 1,” then show the next wave or “All Waves Cleared”), and the count of active plus not-yet-spawned enemies. Center a status message below the top bar, initially “Build a defense, then launch the first wave.” At the bottom center, place a dark rounded control panel containing selection/help text and buttons: Build Tower · 50, Upgrade · cost, Start Wave/current next wave, speed, and a hidden-until-end Restart button. Use cyan as the primary action color, gold for upgrade/gold controls, and slate blue for secondary buttons, with rounded corners, shadows, pressed-button movement, and disabled opacity. Include helper text: “Towers fire automatically. Between waves, tap a tower to select it and spend gold on upgrades. Hold the line for 10 waves.” On narrow screens stack the bottom panel and hide the helper aside while keeping the top stats compact. Maintain the calm navy/cyan/gold/red visual language and rounded neon effects visible in the supplied screenshot.