Crystal Evolution

Crystal Evolution is a top-down mining and tower-defense game. By day you guide your miner across a crystal field, haul five colours of crystal home and spend them on walls, generators and towers. At night the waves come for your base, and every few nights a boss. Survive as long as you can, then spend the Shards you earned on permanent upgrades and suits for the next run.

Features

• Mine five crystal colours; build walls, economy buildings and towers around your base
• Towers branch and evolve into stronger forms as you unlock them
• Day/night cycle with escalating waves and boss nights
• Four difficulties (Easy to Impossible) and a run specialization screen before each run
• Roguelite meta progression: Shards buy permanent upgrades and suits between runs
• Idle mode that keeps mining while you are away
• Online co-op for 2 to 4 players (see below)
• Plays in the browser on desktop and phones (landscape); no download, no account

Co-op multiplayer

One player taps Multiplayer, then Host Game, and shares the 5-letter room code; friends tap Join by Code. The game runs in the host's browser and connects players directly, peer-to-peer (WebRTC). There is no game server and no account. Everyone gets their own miner and base on the same map, the host picks the difficulty and starts the run, and a player who drops can rejoin their slot within 5 minutes. If the host leaves, the session ends. Tested with up to 3 players; the limit is 4. Some strict corporate or school networks block peer-to-peer connections.

Controls

Mouse or touch: tap a crystal to mine it, tap ground to walk there, tap and hold empty ground to open the build menu. Keyboard: WASD or arrow keys to move, P or Esc to pause (solo).

Privacy

No account needed. Progress is saved in your browser only, and the game collects no personal data. Multiplayer connects you directly to the other players' browsers, using the free PeerJS service for the initial handshake. Full policy: responsivedesignllc.netlify.app/privacy/crystal-evolution.html

Made by Responsive Design LLC. Feedback is welcome in the comments.