X Practice is a raid practice addon. It uses World of Warcraft's built-in ModelScene widgets to create a virtual 3D environment where you can practice selected boss mechanics by yourself (or in a group!) without worrying about wiping the raid.
Type /xp to begin. Make sure your character is in a safe place before playing.
To move, use WASD or press the left+right mouse buttons simultaneously. Adjust the camera with the scroll wheel.
Keybinds and screen size can be changed in Config.lua. Additional config files are available in each scenario folder for even more fine-tuning. Try adjusting the difficulty upwards until the real raid seems easy in comparison!