Co-op multiplayer FPS survival template for Unity 6 URP: procedural islands,
gathering, base building, crafting, day/night and per-player saves.
Server-authoritative on Mirror.Island Survival is a complete, ready-to-play co-op survival FPS you can dropstraight into your project — or use as the foundation for your own game.Procedurally generated islands, resource gathering, base building, crafting,day/night, drowning and PvP, all playable in multiplayer over Mirror or fullyoffline on a single machine.The same scripts run both ways. With a session active every system isserver-authoritative; with Mirror not running they apply their effects directly.You never maintain two code paths.WHAT'S INSIDE• Procedural island generation — terrain, trees, rocks and ore from a single seed, with a live island preview in the "New Game" menu• Resource gathering — chop trees, mine rocks and ore, with respawning nodes• Base building — snap-based placement, build menu, destructible pieces• Crafting & server-authoritative per-player inventory with hotbar• Item dropping and loot sacks — walk over them to pick up; dying scatters everything you carried• Day/night cycle with a server-owned clock• Water, drowning and an underwater screen effect• Full-screen island map (M) with grid, zoom, pan and colour-coded markers• PUBG-style compass HUD that shows your map markers at their real bearing• Text chat and proximity voice chat (pure C# codec — no native plugins, no third-party licences)• Complete menu flow: Create Game, Load Game, Create Server, Join, settings, key rebinding, loading screen and pause menu• Save/load system with per-player persistence — position, health, stamina, hotbar, inventory, buildings and harvested resourcesTWO READY-MADE SCENESMAIN MENU and DEMO come fully built and wired — HUD, map, compass, chat, buildmenu and pause menu are already in the scene. Nothing is generated on demand, soreusing a piece of UI in your own scene is a copy-paste: every reference travelswith the object.BUILT FOR MULTIPLAYER, NOT PATCHED FOR IT• Deterministic world, not replicated world. The island is regenerated on every peer from one synced seed — no heightmaps or object lists ever cross the wire.• Id-based resource sync. Nodes get stable ids from generation order instead of a NetworkIdentity each, so hundreds of trees and rocks cost almost nothing.• Late joiners see the world as it is now. A player joining an hour in gets the island rebuilt from the seed, then immediately clears exactly what the others already harvested.• Server-authoritative inventory, crafting, building, dropping and pickup. A modified client cannot conjure items or claim loot twice.• Per-player saves keyed by a persistent id, so a player who quits and rejoins gets their own inventory and position back.EASY TO ADAPT• Every script has detailed XML documentation comments — no black boxes.• No assembly definitions to fight with; everything compiles into Assembly-CSharp.• Editor tools: Rebuild Item Database, Fix Build and Networking Issues, and Validate Multiplayer Setup, which scans your scene and reports exactly what is missing.• Swappable networking backend. Connection code sits behind IMultiplayerConnector and MultiplayerSession — the menu, loading screen and pause menu never name a networking type.• Steam, Epic, Edgegap, relays and mobile are just Mirror Transport components: swap the Transport on the NetworkManager and change no code at all. The Join panel adapts by itself, hiding the port box for backends that use join codes or SteamIDs.• Add your own save data by inheriting SaveableBehaviour with a unique SaveId.SUITABLE FORSurvival, crafting and base-building games; co-op and PvP island/shipwrecksettings; open-world exploration prototypes; anyone who needs a workingserver-authoritative gameplay foundation instead of building netcode fromscratch.REQUIREMENTS• Unity 6• Universal Render Pipeline — included materials are authored against URP/Lit• Mirror networking — FREE on the Asset Store, must be imported firstA 15-page PDF documentation file is included, covering setup, singleplayerconversion, the networking design, every system and its known limitations.Multiplayer:• Server-authoritative gameplay built on Mirror (host / dedicated server / client)• Deterministic world generation from a synced seed — no terrain data sent over the network• Id-based resource synchronisation — no NetworkIdentity per tree, rock or ore node• Late-join catch-up: joining players receive the current harvested state• Swappable backend behind IMultiplayerConnector / MultiplayerSession• Transport-agnostic — works with KCP, Telepathy, FizzySteamworks, Edgegap and relays• Runs fully offline with Mirror never starting — same scripts, no second code pathWorld:• Procedural island generator (terrain, water, coastline) driven by an IslandSettings asset• Seeded spawners for trees, rocks and ore nodes with configurable density• Live island preview in the New Game menu• Networked day/night cycle with server-owned clock and client-side interpolation• Coast spawning — players appear at random shoreline points on join and respawn• Proximity LOD system for spawned world objectsPlayer systems:• First-person character controller (walk, sprint, jump, crouch)• Health, stamina and oxygen with drowning damage and underwater screen effect• Per-player server-authoritative inventory (24 slots) and hotbar (8 slots)• Crafting system driven by ScriptableObject recipes• Snap-based building system with destructible pieces and a build menu• Wall-mounted placeables (torches) with server-side validation• Item dropping, loot sacks with walk-over pickup, and full inventory drop on death• Melee tools and weapons (axe, pickaxe, swords) with tiered gatheringUI:• Two complete scenes: MAIN MENU and DEMO, fully wired• Create Game / Load Game / Create Server / Join Game flow• Full-screen island map with grid, zoom, pan and colour-coded markers• Compass HUD showing map markers at their real-world bearing• Networked text chat and proximity voice chat with self-tuning jitter buffer• Settings with graphics, audio, microphone picker and key rebinding• Loading screen with fallback camera and real handover progress• Pause menu with in-game savingSaving:• Slot-based save/load system, host-authoritative in multiplayer• Per-player persistence keyed by a persistent GUID — survives quit and rejoin• Saves island seed, time of day, harvested resources, buildings, wall mounts, and each player's position, rotation, health, stamina, hotbar and inventory• Extensible: inherit SaveableBehaviour with a unique SaveId to add your own dataCode & tooling:• ~95 C# scripts, all with XML documentation comments• No assembly definitions — compiles into Assembly-CSharp• Editor tools: Rebuild Item Database, Fix Build and Networking Issues, Validate Multiplayer Setup• Input System based, with runtime rebinding saved to PlayerPrefs• 15-page PDF documentation includedVoice chat:• Pure C# IMA ADPCM codec at 16 kHz (~8 KB/s per speaker) — no native plugins• Server-enforced proximity range with linear falloff• Push-to-talk with lead-in and tail so the first and last word aren't clipped• Live microphone level meter and device pickerChatGPT was used to generate some of the textures and Claude to help optimise the C# scripts.
