The Ultimate Guide to Creating a Tower Defense Game in Unity

Install Unity using Unity Hub, choose the 2022 LTS version, and create a new 3D core project named Udemy course tower defense to start your tower defense development.

Import prototype materials and build a testing ground with simple shapes, then assemble a tower and an enemy, using a parent body and a rotatable head for C sharp practice.

Create a Unity tower script that references the enemy transform and tower head, uses look at and distance checks, and visualizes attack range with gizmos.

Instantiate a bullet prefab at the tower head, then propel it toward the enemy by calculating the direction, normalizing it, and applying velocity to the bullet’s rigidbody.

Use Unity's OnTriggerEnter to damage enemies when bullets enter a trigger, destroy both the enemy and the bullet, tag enemies, and refactor with a create bullet method.

Learn how to store multiple enemies in one variable using arrays and lists in Unity, access them by index, select a random target, and dynamically manage targets with a list.

Learn to use a for each loop to iterate through enemies in a list and find the closest to the tower by comparing distances within the attack range in Unity.

Use a for loop to spawn multiple enemies in Unity for a tower defense game, using an enemy creator, instantiating a prefab, randomizing positions, and tracking enemies in a list.

Learn how access modifiers differentiate public and private members, and implement encapsulation by using serialized private fields and a getter method to protect data while keeping it accessible.

Solidify your foundation in unity and scripting from the crash course and prepare for the main lessons to come. Look ahead to a new project in the next section.

Learn to smooth enemy rotation in Unity by facing the movement direction with horizontal rotation only, using direction to target, quaternion look rotation, and time.deltaTime for frame-rate independent turn speed.

Create a rotate object script to rotate wheel objects on the x-axis at a frame-rate independent speed, and test with two enemies using two-waypoint paths.

Implement a waypoint manager in Unity to fix enemy references to waypoints, build an enemy prefab, and load waypoints via a get waypoints method so new enemies receive the path.

Learn to detect enemies within a tower's attack range using a physics overlap sphere, draw gizmos, implement a random target within range, and handle null targets safely.

Implement raycast detection to find enemies from the crossbow’s gun point, compute a normalized direction to the target, and trigger an attack with recoil visuals.

Create tower attack visuals by using a line renderer with an emission blue laser, control laser duration with a coroutine, and disable rotation to sync visuals with the attack.

Learn to create a glow effect for a crossbow tower in Unity using a coroutine loop that lerps emission intensity over cooldown, with material instancing and a mesh renderer.

Learn to make a cross bolt tower glow by dynamically changing its emission color with intensity using color lerp and a coroutine, with start color, end color, and gamma-space correction.

Learn to center a tower’s targeting by adding an enemy center point in Unity, using an enemy component, center point transform, and update‑driven visuals for precise, responsive attacks.

Define enemy type with enum, create priority targets and possible targets lists, and ensure priority targets are targeted first, with fallback to possible targets.

Fix tower shooting through obstacles by refining raycast hit detection and enemy targeting, and switch to mesh colliders for precise collision in Unity.

discover a tile-based level creation system that speeds up level design by swapping tile meshes and materials through a tile slot, enabling corners, bridges, and enemy routes.

Create a Unity custom editor button to toggle a tile slot property and wire it to the tile slot script, supporting multi-object editing with targets and serialized object update.

Update tile visuals using a grid builder and tile set holder to switch meshes and materials from reference tiles, including road, field, and sideway. Learn editor setup and slot logic.

Fix missing tiles by building a five-by-five grid, add inner and outer corner small tiles, and update the grid builder prefab and tile set for Unity tower defense.

Upgrade the waypoint system and wave management to create different paths for waves of enemies, implement clean-up steps, and refine prefab handling for a reusable tower defense project.

Improve the waypoint system by giving each portal a dedicated waypoint set and collecting those waypoints from portal children into the enemy portal’s list via a setup method.

Improve waypoint navigation for enemies by dynamically selecting the next waypoint based on distance, refactoring waypoint management, and ensuring smooth pathing in a Unity tower defense game.

Create and manage multiple enemy waves in Unity by converting wave details to an array of level waves, tracking with a wave index, and triggering next waves with bounds checks.

Discover how to align enemy visuals to slope surfaces in Unity by raycasting for the ground normal and smoothly rotating visuals via quaternion slerp.

Archive the project and attach it to the video. Download it for verification, and thank you—see you in the next video.

Create a custom Unity camera controller using the old input system to pan, rotate, and fly around a field with smooth damped movement, plane-constrained forward, and keyboard or mouse input.

Master camera rotation in Unity by rotating around a focus point with mouse input, using a rotation speed and vertical pitch clamp, plus raycast-driven focus point alignment.

Set camera boundaries by anchoring to the level center and clamping target position within a maximum distance, using center-to-target direction and vector normalization for keyboard, mouse, and edge movement.

Create an in-game ui with hp, timers, and main menu. Import fonts, borders, icons, and textures; enable Text Mesh Pro and 2D sprite package in Unity.

Lay out the menu in Unity with a canvas and scalable screen. Add play, settings, and quit buttons with TextMesh Pro and sliced borders for level selection.

Learn to switch between menus in Unity using a UI manager that toggles visibility for main menu, settings, credits, and level selection, with back and quit functionality.

Set up a credits UI in Unity and add a hyperlink button to promote links like a YouTube channel or website, using a simple script to open the URL.

Create settings UI logic in Unity to control camera sensitivity with keyboard and mouse sliders, use lerp for smoothing, and persist values with PlayerPrefs.

Implement settings UI logic for mouse and keyboard sensitivity in Unity, using sliders and TextMeshPro text displays to show percentages, with load/save via PlayerPrefs and initial awake initialization.

Create an in-game health points (thread) display, wire it to a game manager that tracks max hp and current hp, and update the UI as enemies enter the castle.

Learn to animate UI buttons with a hover scale effect using a UI animator and coroutines, applying a single scalable coroutine per button and handling pointer enter/exit events.

Clean up the Unity tower defense UI by renaming settings UI and main menu UI, keeping a functional project ready for archiving and reuse.

Develop a build manager for tower placement and level transitions with fade effects and in-world level buttons. Prototype tile-based tower building with hover indicators and tile movement via a coroutine.

Create a centralized Unity build system by wiring UI build buttons to the build manager, enabling the build menu on tile selection and spawning a tower atop the tile.

Display a tower's attack radius using a line renderer to draw a circular radius around the tower, using 50 segments to visualize range in Unity.

Build a tower preview system in unity by converting a tower to a non-attacking preview, showing an attack radius, and enabling tile-based tower placement with preview visuals.

Learn to implement build-system hotkeys in Unity by reading keyboard input, mapping number keys to unlocked build buttons, and confirming builds with space.