there is the hard way and the easy way. also, you need an Item with 4 Sockets to create a Mythic Affix. when you make the recipe, all 4 Mythstones and the Sockets they are in are replaced by the Mythic Affix.
Hard Way: Floor 21 and higher is when Mythstones start to drop. when you find Items you are going to sell for Gold that have Sockets on them, put Mythstones you don’t need in them for a chance to reveal part of a Mythic Affix recipe. higher Tier Mythstones give a higher chance for a revealed recipe part. this takes time but is a fun part of the game.
Easy Way: here are all the recipes.
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