Galaxic

Overview

A Galaga-inspired arcade shoot-em-up built from scratch in Unity. Enemies fly in formation, break off to dive-bomb the player using emergent steering behaviors, coordinate squad attacks, and scale in difficulty across an unbounded level progression. Every 10 levels ends in a boss encounter — five distinct boss archetypes with rage phases and a desperation mode.

The focus of this project was game AI: rather than scripted patterns, enemies reason about the player using a behavior tree + Craig Reynolds steering pipeline, giving each dive a different feel without manual choreography.

Features

• Swarm AI with token-based coordination — A SwarmDirector singleton manages the formation grid, caps simultaneous divers via a token budget, and coordinates column and wingman squad attacks with configurable timing
• Hybrid enemy locomotion — Formation entry and retreat use cubic Bézier splines; active dives switch to a real-time steering agent (Seek, Evade, Wander, Separation) driven by a behavior tree
• Bullet-aware evasion — Diving enemies scan for nearby player bullets each frame and react with evade steering or an emergency dive abort
• Logarithmic difficulty scaling — All 20+ parameters (grid size, bullet speed, fire rate, enemy type weights, squad cooldowns) ramp asymptotically, tuned so difficulty stretches across 80–130 levels rather than peaking at 15
• Four enemy archetypes — Standard, Gunner (rapid-fire), Kamikaze (aggressive pursuit), Sniper, and Juggernaut (multi-hit) unlock and grow in weight as levels increase
• Five boss types with rage phases — TripleShot, Charger, Shield (immune phases), Minion (drone spawner), and Mixed; each has two rage thresholds and a desperation burst at 15% HP
• Between-level upgrade shop — Persistent coins fund shield stockpiles, fire-rate boosts, and tri-shot charges; upgrades survive game-over continues
• Persistent save system — JSON serialization tracks highest level reached, coin balance, and upgrade inventory across sessions

Stack

• Unity 6
• C#
• Universal Render Pipeline
• Behavior Trees
• Craig Reynolds Steering
• Bézier Splines
• Unity Input System
• Physics2D
• JsonUtility

Links

• Google Play