Dispersion
Instant
2 min cooldown

You disperse into pure Shadow energy, reducing all damage taken by 90%. You are unable to attack or cast spells, but you regenerate 6% mana every 1 sec for 6 sec. Dispersion can be cast while stunned, feared or silenced and clears all snare and movement impairing effects when cast, and makes you immune to them while dispersed.
Fuente: Dispersion - Spell - World of Warcraft

Deberia de limpiarte los efectos que te impidan moverte o que te hagan ir mas lento y hacerte inmune a ellos durante los 6 segundos.

A veces pasa que cuando tiras dispersion JUSTO cuando te entran los CC o daños te los comes igual.

In PvP, it will give you 6 seconds of additional survival. You can still be silenced, trapped, feared, stunned, and the like, and rogues and druids have 6 seconds to get 5 combo points on you. So expect no survival after Dispersion wears off.
No dice nada de ciclon pero te vas dando una idea de como funciona.

Saludos Az!