Frostline 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 3D top-down tower defense game called "Frostline Defense" with the following specifications:

**Camera & Perspective**: Fixed isometric top-down view from an elevated angle (camera at position 0, 14.5, 14 looking at 0,0,0) showing the entire battlefield. Use Three.js with perspective camera, shadows enabled, and fog for depth.

**Visual Style**: Low-poly 3D with shadowed meshes. Scene has dark blue gradient background (0x102033) with atmospheric fog. Use Kenney CC0 tower defense models for tower bases, cannon toppers, and four UFO enemy variants. Ground is dark green/brown textured plane with tan/beige path segments. Towers have distinct colored cylindrical/cone toppers with glowing range rings when selected. Enemies are UFO models or colored geometric shapes (spheres, boxes) with identifying features: speed rings, tank bulk, stun horns, boss crowns, ice crystals. Bullets are small colored spheres. HUD uses clean sans-serif white text on dark semi-transparent panels.

**Core Mechanic**: Player places defensive towers on open ground (not on enemy paths, bases, or spawns) to stop waves of enemies traveling along predefined curved paths from spawn gates (red boxes) to the player's green base. Base starts at 100 HP; enemies that reach the end deal their remaining HP + 5 as damage. Lose at 0 HP.

**Tower System**: 
- Before each match, pick a save file and choose up to 5 unit types for your loadout from owned towers
- During gameplay, place towers anywhere on open grass (minimum 1.05 unit spacing between towers)
- Live placement preview shows green footprint/range ring when valid, red when blocked
- Towers have individual costs (90-2600 gold), ranges (shown as torus rings), damage, cooldown, and color-coded projectiles
- Each tower has 2-6 upgrade paths with 3-6 levels per path; most lock to one path after first upgrade
- Pistoler (starter, blue) has damage path (max 40 dmg, slower shots) or speed path, can take 2 upgrades in non-main path
- Starter (green, 200 coin shop tower) has focus/range/rapid paths with 6 upgrades each
- Bomber (orange, unlocked by Easy mode) has AOE or speed paths, max 3 per match
- Sniper (cyan, unlocked by Normal) has extreme range, damage (6s cooldown at max), or defense-break paths, max 5
- Scrapper (gray, unlocked by Hard) is unique max-1 tower generating scrap resource with 4 exclusive paths including self-stun ability and passive scrap generation
- Snowmancer (ice blue, unlocked by Winter, max 1, 2500 cost) summons snow allies with three long exclusive paths
- Factory (gray, max 1, 1500 cost) uses side-menu to buy up to 20 summons (Brick Layer 300g, Box Pusher 500g, Milk Tosser 425g; after maxing: Nail Gunner 550g, Metal Pusher 1000g, Molotov Tosser 700g)
- Additional shop towers: Sparkmage (purple chain lightning or charged bolts), Cryogunner (cyan freezer), Medic (green support booster), Chronomancer (purple time mage), Flamethrower (red short-range AOE), Ranger (green bow), Shaman (teal spirit caster), Goldsmith (yellow economy attacker with kill cash bonus), Bastion (red heavy with armor break/splash/overwatch paths), General (yellow support with damage/tempo buffs, max 1), Investor (yellow non-attacking economy tower, max 4, generates gold over time with dividend or bounty paths), Trapper (green, passively lays 15 traps on nearby path tiles, max 2), Pylon (cyan chain lightning hitting up to 4 enemies, can hit floating, max 2), Reaper (purple zombie summoner from Manor, max 1), Alchemist (teal hidden Manor flower reward, makes potions, max 1), Priestess (pink orb summoner, challenge reward, max 1), Void Warden (purple space controller from Abyssal Rift, void/gravity/shield paths, max 1)
- Many towers have alternate skins unlocked from submodes with stat tweaks (Storm Sparkmage, Redoubt Bastion, Commander Pistoler with backup soldiers, Meadow Starter with slow, Starcaller from Outerspace, Mines Worker investor variant, etc.)
- Towers show distinct silhouettes via toppers: cannons, orbs, cubes, spikes, totems, magic effects
- Selected towers display visible green range ring scaled to range; side panel shows upgrade paths and sell option (65% refund)
- Summons: some towers spawn ally units (Factory workers, Snowmancer snow allies, Reaper zombies, Commander Pistoler backup soldiers) that walk down path and collide with enemies using HP-vs-HP damage until one dies. Ranged summons stop to shoot.

**Enemy Types**: 
- Normal (red UFO, standard HP/speed, 16 cash)
- Speedy (yellow UFO, low HP, fast, 12 cash) with speed rings
- Tank (purple UFO, high HP, slow, 30 cash, 2 defense) bulkier
- Stunner (purple with horns, stuns all towers 4s on death, 24 cash)
- Floating (cyan UFO, flies, requires air-targeting towers, 26 cash)
- Boss types (larger, crowns, 650-10000 HP, 8-16 defense): standard pink boss, hard mode boss with pulse-stun, gem boss with gem-body mechanic, Star boss (yellow floating), Frost Titan, Virtue (holy boss with summons/stuns/range debuffs), Zombie Boss with 3 lives, Glitch Boss, Icemancer summoning boss
- Winter enemies: snow (splits on death), ice (fast slide), icemancer, frost titan phases
- Manor enemies: zombies that revive once, husks revive twice
- Mines enemies: mine variants, gemstone (high defense), gem blockers (stationary 40HP obstacles), gem boss
- Outerspace: mostly floating space enemies
- Holy enemies (yellow/white, cannot be slowed/stopped, keep moving briefly after death, +50% cash)
- Glitch enemies (color-cycling magenta/cyan)
- All enemies scale HP with wave number; Hard mode adds +40% speed and +30% HP; Endless stacks speed every 10 waves

**Resources**:
- In-game GOLD: starts at 650 (1000 in Hard, 1350 in Winter), earned from enemy kills (base cash + tower bounty bonuses), used to place and upgrade towers
- Out-of-game COINS: earned from clearing modes (50-1200 coins), used in shop to buy new tower types permanently
- SCRAP: generated by Scrapper tower, capped at 500, used for Scrapper upgrades alongside gold
- Hidden code "no more credz" grants 500 coins to active save

**Game Modes** (with distinct map layouts, prop colors, path curves):
- Tutorial (1 wave, hidden after clear)
- Easy (10 waves, unlocks Bomber, rewards 50 coins) with 5 submodes: Meadow Rush, Brook Bend, Orchard Run, Lantern Trail, Training Field (12 waves each, 100 coins, unlock skins)
- Normal (15 waves, stunner at wave 10, boss at 15, unlocks Sniper, 250 coins) with 6 submodes: Stormforge, Redoubt, Drill Camp, Forgeyard, Wildgrove, Oracle Run (16 waves, unlock skins) plus The Mines (20 waves, dark underground props, mine enemies from wave 6, gemstone blockers, +20% kill cash, gem boss wave 20, unlocks Mines Worker) and Outerspace (15 waves, starfield props, mostly floating enemies, +1000 gold every 5 waves, Star boss wave 15, unlocks Starcaller)
- Hard (25 waves, requires Normal clear, +40% enemy speed/+30% HP, first 3 waves spawn 5 fewer basics, bosses at 15 and 25, unlocks Scrapper and Endless, 350 coins) with submodes: Manor (30 waves, Halloween styling, two paths, zombies revive, hidden flowers unlock Alchemist, zombie boss wave 30), Arcade (compact 30 waves, glitch enemies and boss), Abyssal Rift (32 waves, unlocks Void Warden), Voidworks, Crystal Keep, Frosthold (30 waves each, unlock skins)
- Winter (45 waves, hidden until Easy/Normal/Hard cleared, escalating snow overlay, snow split enemies, ice enemies, Icemancer, Frost Titan phases, 1000 coins) with submode Heaven's Gate (45 waves, holy enemies, +50% cash, 2 retries after wave 36, Virtue boss wave 45, 1200 coins)
- Endless (up to wave 100, unlocks after Hard, speed stacks every 10 waves, 55 coins every 11 waves)
- Maps have decorative props: cones and boxes colored per mode, mines with rail ties and glowing crystals, manor with pumpkins and gravestones, outerspace with glowing stars, meadow with pink flowers, winter with snowman models

**Wave Mechanics**: 
- Waves spawn from red gate(s) at path start
- Click Start Wave button to begin (auto-start toggle available)
- Enemies follow curved multi-segment paths (some maps have dual paths like Manor)
- 1-2 second delay between wave completion and next wave availability
- Fast-forward toggle: 1x / 2x / 3x speed multiplier affects spawning, movement, attacks, summons
- Display shows: Wave X/Y, Gold, Base HP, scrap (if Scrapper placed)

**Combat**:
- Towers auto-target furthest-progressed enemy in range (prioritize stationary at 999)
- Projectiles fly from tower to target, deal damage on hit
- Some towers have AOE damage radius, chain lightning (Pylon jumps to 4 enemies with falloff), splash, armor break (reduces enemy defense), slow effects, stun traps
- Defense reduces damage: damage - defense (minimum 1)
- Breaker stat multiplies defense reduction
- Buff system: General/Medic boost nearby tower damage/speed for duration
- Debuffs: tower stuns from stunner enemy death or boss abilities, tower range debuffs from Virtue boss
- Trapper lays up to 15 traps on nearby path tiles with 1.15 unit spacing; enemies trigger on touch (AOE mines, slow spike traps, stun bear traps)

**HUD Elements**:
- Top bar: wave counter, gold display, base HP bar (green, turns red when damaged), Start Wave button, Auto-Start toggle, speed buttons (1x/2x/3x), menu button
- Bottom tower bar: clickable unit portraits from loadout (shows cost, grayed if unaffordable or placement limit reached)
- Right side panel (when tower selected): tower name, level/path display, three upgrade path buttons with costs and descriptions, Sell button
- Factory towers show special side panel with summon purchase buttons (Brick Layer/Nail Gunner, Box Pusher/Metal Pusher, Milk Tosser/Molotov Tosser)
- Toast notifications: brief centered messages for income, unlocks, errors
- Snow overlay div with animated falling snow for Winter mode

**Progression System**:
- LocalStorage saves support 3 starter slots, up to 20 total
- Saves track: coins, cleared modes, badges (27 types: mode clears, Ascension from 5% stun event, Alchemist from clicking 4 hidden manor flowers), owned units, loadout
- Shop screen: grid of unit cards showing name, description, coin cost, "Buy" or "Owned" button
- Loadout screen: drag/click to pick up to 5 units for next match from owned units
- Badge screen: display earned badges as cards
- Main menu: Start Mode button (opens mode picker), Shop, Loadout, Badges, Save Select
- Mode screen: list of unlocked modes with descriptions, wave counts, rewards, lock status
- Clear modes to unlock new modes and tower types sequentially

**Controls**:
- Mouse/touch: click tower bar portrait to enter placement mode, click ground to place tower, click placed tower to select, click side panel buttons to upgrade/sell, click Start Wave
- Pointer events show live green/red placement preview following cursor when placing
- Click menu button to return to main menu (game pauses)

**Audio**: 
- Kenney CC0 click SFX for UI interactions (0.45 volume)
- Kenney CC0 laser SFX for tower shots (0.12 volume, throttled to 120ms)

**Win/Lose Conditions**: 
- Win: survive all waves with base HP > 0, award mode coins and unlock rewards
- Lose: base reaches 0 HP (even if final boss dies simultaneously)
- Victory shows gold earned, rewards unlocked; defeat shows final wave reached

**Special Mechanics**:
- Gem boss: has separate gem body parts that must be destroyed first
- Holy enemies: immune to slow/stop, keep moving after death briefly
- Zombie revival: stand back up with reduced HP after first death
- Split enemies: spawn smaller enemies on death
- Stunner death: 4-second global tower stun (5% chance grants hidden Ascension badge)
- Virtue boss: summons minions, stuns towers, applies range debuffs
- Glitch enemies: rapid color cycling animation
- Manor flowers: 4 hidden dark cone flowers on map, clicking all 4 unlocks Alchemist
- Mines: gemstone blockers are stationary 40HP obstacles on path
- Factory menu: shows current summon count / 20 limit
- Winter snow overlay: escalating visual snow effect
- Heaven's Gate retries: after wave 36, base gets 2 extra chances at 0 HP

Design ground-truth: towers have colored geometric toppers (cylinders, cones, spheres, boxes) on round bases. Enemies use UFO models (4 variants) or colored primitive shapes with scale/marker variations. Paths are tan curved segments on green/brown ground. Maps have mode-colored decorative props (cones, boxes, pumpkins, crystals, stars, flowers, snowmen). UI is clean dark panels with white text. Camera never moves. All visual details match low-poly Three.js aesthetic with shadows and emissive glows.