Space Invaders
Classic Space Invaders arcade game. Defend Earth from descending alien formations (V-shape, diamond, spiral)! UFOs drop power-ups 100% of the time, and a BOSS appears every 4 levels!
How to Play
Use arrow keys or A/D to move, Space to shoot. Shoot down UFOs to collect power-ups (shield / rapid / spread / pierce / double). A BOSS appears every 4 levels. Destroy all aliens before they reach the bottom.
Objective
Control your ship at the bottom of the screen to shoot and destroy the alien formation above. Formations come in multiple shapes: classic, V-shape, diamond, double-diamond, spiral (L9) and more. Aliens move side to side and descend when they reach the edge. If any alien reaches your row, the game is over. Clear all aliens to advance to the next level. New tank enemies have 2 HP, move slower, and are worth 60 points. A BOSS (5 HP, fires back) appears every 4 levels. UFOs drop a power-up 100% of the time when destroyed: shield (1-hit protection), rapid (8s 2x fire rate), spread (8s 3-way shot), pierce, or double.
Controls
• Keyboard: A/D or Left/Right Arrows to move • Keyboard: Space to shoot • Keyboard: P to pause, R to restart • Mobile: Use the left/right buttons and fire button • Switch between 2D and 3D views anytime • You can only have one bullet on screen at a time • Bunkers shield you but are destructible by both your and alien fire
Tips & Strategy
• Pick off the bottom-row aliens first — they're closest to your line • Aliens speed up as fewer remain — clear them efficiently • Use bunkers for cover, but they erode with each hit • The UFO bonus ship appears periodically — shooting it drops a power-up (shield / rapid / spread / pierce / double) 100% of the time • Squid (top, small) = 10 pts, Crab (middle) = 20 pts, Octopus (bottom) = 30 pts • Tank aliens (gray) have 2 HP and move slower — worth 60 pts • Time your shots — you can only have one bullet on screen (fire rate doubles with rapid power-up) • In later levels, aliens start lower and fire more frequently • A BOSS (red giant alien, 5 HP, fires back) appears every 4 levels — prioritize killing it • Power-up effects: shield absorbs 1 hit, rapid grants 8s of 2x fire rate, spread grants 8s of 3-way shots • Spiral formation appears from L9 — dense but with gaps