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+++ b/README.md
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-# mixsy 
+# Mixsy
 
-blah blah blah
+A tool for combining Bitsy games.
+
+Paste your game data into the main and additional inputs, and click _mix_!
+
+All palettes, rooms, tiles, sprites, items, exits, endings, variables and dialogue 
+will be copied from the additional game to the main game. 
+Tiles will also be deduplicated, to avoid unnecessary extra tiles in your merged game. 
+The resulting merged game will appear in the output box. 
+You can copy and paste this back into Bitsy.
+
+I'm fairly confident that Mixsy won't mangle your game data, 
+but I still recommend taking backups of your games periodically.
+
+Mixsy requires WebAssembly, so if it doesn't work on your web browser 
+I suggest using [bitsy merge](https://seansleblanc.itch.io/bitsy-merge) instead.
+
+# Credits
+
+A tool by Max Bradbury
+
+Thanks to Adam Le Doux for Bitsy
+
+Thanks to Freya for the colour palette (I love that watermelon and mint-choc-chip kinda thing)
+
+Thanks to Candle, Sean and everyone in the Bitsy community