Comprehensive NPC System - Server-Authoritative with Client Optimization
A production-ready, highly flexible NPC system that provides server-authoritative NPCs with client-side rendering optimization, advanced pathfinding, sight detection, and behavior systems. Built for scalability and performance!
For tower defense games
For ranged NPCs:
- NPC strafes as soon as it gets to appropriate distance
- sight detection (wonât detect you if a wall is there)
- when idle, they will randomly move and with default animations loaded. (usually NPCs donât have default animations loaded)
NPC types such as melee, unmoving NPCs, direction-sight NPCs
- Melee will be persistent until you move out of their range.
- Unmoving NPCs wonât move while still able to target you, perfect for tower defensegames.
- Direction-sight wonât see you and target you until they see you!
Why Use This System?
Production-Ready Architecture
- Server-Authoritative Design - Full server control over NPC behavior and state
- Modular Component System - Extensible architecture for easy customization
- Clean Code Organization - Server/Client/Shared separation
Performance & Optimization
- Client-Side Rendering - Optional visual rendering reduces server load significantly
- Distance-Based Culling - NPCs only render when players are nearby
- Batch Hitbox Operations - Efficient spawning and management, useful for tower defense games (future implementation)
- Scalable to 1,000+ NPCs - Tested and optimized for large-scale games (future implementation)
- Animation integration for NPCs (using an improved BetterAnimate library)
Advanced Features Out-of-the-Box
- Dual Sight Modes - Omnidirectional (360°) and Directional (cone-based) detection
- Smart Pathfinding - Integrated NoobPath library with obstacle avoidance, can be disabled
- Idle Wandering - NPCs can randomly explore when idle
- Combat Movement - Dynamic strafing during target engagement for ranges, and normal movement for melees
- Visual Debugging - Built-in sight visualization tools
- Faction System - Prevent ally targeting
Developer-Friendly
- Easy Integration - Simple spawn/destroy API
- Example Test Scripts - Ready-to-run learning examples
Installation
Method 1: SuperbulletAI (Fastest - 60 seconds!) 
- Download SuperbulletAI
- Prompt:
add npc system to my roblox game - Done! The AI automatically integrates everything
Method 2: Download RBXL Place File 
Perfect for testing and learning:
- Download
npc_system_place.rbxlfrom the GitHub Repository - Open in Roblox Studio
- Explore pre-configured test scenarios
- Copy source files to your game when ready
Method 3: GitHub + Rojo (For Developers) 
For version control and advanced development:
- Clone:
git clone https://github.com/Froredion/Comprehensive-NPC-System.git - Install Rojo: rojo.space
- Build and sync:
rojo serve - Connect from Roblox Studio using Rojo plugin
đ Quick Start Example
local ReplicatedStorage = game:GetService("ReplicatedStorage")
local Knit = require(ReplicatedStorage.Packages.Knit)
-- Wait for Knit to initialize
Knit.OnStart():await()
local NPC_Service = Knit.GetService("NPC_Service")
-- Spawn a basic NPC
local myNPC = NPC_Service:SpawnNPC({
Name = "BasicNPC",
Position = Vector3.new(0, 10, 0),
ModelPath = game.ReplicatedStorage.Assets.NPCs.Characters.Rig,
-- Stats
MaxHealth = 100,
WalkSpeed = 16,
JumpPower = 50,
-- Behavior
SightRange = 60,
SightMode = "Directional",
MovementMode = "Ranged",
EnableIdleWander = true,
EnableCombatMovement = true,
})
-- Set a target
local player = game.Players:GetPlayers()[1]
if player.Character then
NPC_Service:SetTarget(myNPC, player.Character)
end
âď¸ Configuration Parameters
NPC_Service:SpawnNPC({
-- Identity
Name: string, -- NPC name
Position: Vector3, -- Spawn position
Rotation: CFrame?, -- Optional rotation
ModelPath: Instance, -- Character model path
-- Stats
MaxHealth: number?, -- Max health (default: 100)
WalkSpeed: number?, -- Speed in studs/sec (default: 16)
JumpPower: number?, -- Jump power (default: 50)
-- Detection
SightRange: number?, -- Detection range (default: 200)
SightMode: string?, -- "Omnidirectional" or "Directional"
-- Movement
CanWalk: boolean?, -- Enable/disable movement (default: true)
MovementMode: string?, -- "Ranged" or "Melee" (default: "Ranged")
MeleeOffsetRange: number?, -- Melee distance offset (default: 3-8)
UsePathfinding: boolean?, -- Advanced pathfinding (default: true)
EnableIdleWander: boolean?, -- Random wandering (default: true)
EnableCombatMovement: boolean?, -- Combat movement (default: true)
-- Client Rendering (Optional)
ClientRenderData: {
Scale: number?, -- Visual scale (default: 1.0)
CustomColor: Color3?, -- Color tint
Transparency: number?, -- 0 = opaque, 1 = invisible
}?,
-- Custom Game Data (Optional)
CustomData: {
Faction: string?, -- Faction identifier (e.g., "Ally")
EnemyType: string?, -- Combat type (e.g., "Ranged")
-- Add any game-specific attributes
}?,
})
đĄ Usage Examples
Example 1: Basic Ranged Enemy (with strafe movement!)
local rangedEnemy = NPC_Service:SpawnNPC({
Name = "RangedEnemy_1",
Position = Vector3.new(0, 10, 0),
ModelPath = ReplicatedStorage.Assets.NPCs.Characters.Enemy,
MaxHealth = 100,
WalkSpeed = 16,
SightRange = 60,
SightMode = "Directional",
MovementMode = "Ranged",
EnableIdleWander = true,
EnableCombatMovement = true,
CustomData = {
Faction = "Enemy",
EnemyType = "Ranged",
},
})
Managing NPCs
-- Get NPC data
local npcData = NPC_Service:GetNPCData(myNPC)
print("NPC Health:", npcData.Health)
-- Get current target
local currentTarget = NPC_Service:GetCurrentTarget(myNPC)
-- Manually set target
NPC_Service:SetTarget(myNPC, player.Character)
-- Manually set destination
NPC_Service:SetDestination(myNPC, Vector3.new(100, 0, 100))
-- Destroy NPC
NPC_Service:DestroyNPC(myNPC)
Planned Features (Not Yet Implemented)
UseAnimationController - Client-Side Physics Optimization
Status:
In Planning
An advanced optimization for 1000+ NPCs with minimal lag by offloading physics to clients.
Features:
- Client-side physics simulation
- Client-side pathfinding
- Server stores only positions and health
- 70-95% network traffic reduction
Trade-off: Client has position authority (no validation). Not recommended for combat NPCs.
Use Cases: Ambient NPCs, background characters, non-critical entities
EnableOptimizedHitbox - Batch Hitbox Detection
Status:
Client-side batch hitbox detection for high fire rate scenarios.
Features:
- Batch detection for rapid-fire weapons
- Accumulate hits over 0.1-0.2s window
- Single network call for multiple hits
- Ideal for tower defense with many turrets
Trade-off: Client handles hitbox detection (exploitable). Suitable for PvE, not competitive PvP.
Use Cases: Tower defense games, PvE with rapid-fire weapons, 50+ NPCs
Performance
Current System Capabilities
- 50-100 NPCs - Smooth performance on most servers
- Client-Side Rendering - Distance-based culling reduces load
- Optimized Pathfinding - Intelligent waypoint handling
- Efficient Detection - Cone and magnitude checks
Performance Tips
- Adjust Render Distance - Lower
MAX_RENDER_DISTANCEfor better FPS - Limit Rendered NPCs - Set
MAX_RENDERED_NPCSbased on hardware - Disable Visualizers - Turn off in production (see below)
- Use Faction System - Reduces unnecessary targeting checks
Contributing
This is an open-source project. Contributions welcome!
Areas for Contribution
- Implement UseAnimationController optimization
- Implement OptimizedHitbox batch detection
- Add more movement behaviors
- Create additional sight detection modes
- Improve pathfinding algorithms
- Add example scripts
- Performance optimizations
Development Guidelines
- Follow modular component architecture
- Maintain server authority for critical systems
- Document all configuration parameters
- Test with 100+ NPCs
- Consider both PvE and PvP use cases
This NPC system was from our previous game, we took it and heavily optimized to be customizable.
This was a 1-day project, thereâs still many areas of improvement that can be done!
Resources
- Framework: SuperbulletFrameworkV1-Knit
- GitHub Repository: Comprehensive-NPC-System
- Full Documentation: Available in GitHub repository
Credits
- SuperbulletFrameworkV1-Knit - Robust Knit-based architecture
- NoobPath - Advanced pathfinding capabilities
- BetterAnimate - Smooth animation handling (modified version)
- Roblox Community - Feedback and support
Support & Feedback
If you use this system in your game, Iâd love to hear about it! Feel free to:
- Share your experiences in this thread
- Report issues on GitHub
- Suggest improvements or features
- Ask questions about implementation
Made with 
for the Roblox development community
Version 1.0 - October 2025
