WoW:MACRO mountspecial

/mountspecial is a slash command causing your mount or druid Flight Form to perform a special stunt, depending on the mount. For ground mounts, this animation can be triggered while standing and pressing the space bar, but for flying mounts, only the slash command can be used. As of Patch 2.2, this function cannot be used anymore while moving (excluding taxi mounts, which still use their 'hovering' animation then).

List of stunts per mount type

• Horses, Rams, Elekks, Mechanostriders, and Talbuks: rear up
• Sabers: roar
• Kodos and Wolves: throw the head from side to side with a roar
• Wyvern: roar
• Nether Drake: rear up
• Flight Forms: perform a loop
• Hawkstriders: Flap wings, stretch neck and "roar"

Note: though some animations imply the mount makes a noise - for example, "roars" - only a few make a noise.

Macro to make this command more readily usable

To make the command more "on the go", you can try making a macro like this:

/script UIErrorsFrame:UnregisterEvent("UI_ERROR_MESSAGE");
/mountspecial
/script UIErrorsFrame:RegisterEvent("UI_ERROR_MESSAGE");

and then mapping it to ctrl-space, which normally is unoccupied. Unhooking the errors is done so you don't get errors if you hit the buttons while moving.