Samples
Learn Excalibur by referencing these sample games.
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UI with HTML/CSS/JS
Example of how to build vanilla html/css/js UIs with Excalibur code. The main gist is to put an HTML layer above the canvas layer and use that for UI.
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Tiny Tactics
High fidelity example of a tactics game, with multiple levels, AI, and pathfinding!
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Matter.js
This is a small sample showing how to wire in a 3rd party physics instead of using Excalibur.
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Electron Template
This is a template to show Electron integration with Excalibur. Useful for shipping games to desktops or steam!