Model changes race IN game

[ripper99]

Hey there, im a little new to all this so i hope i am posting in the right place. I currently have an Undead Male char and want to try out some model changing but have noticed in some pvp movies which i have seen there models change between races/sex's in game =/. I havent read anywhere about how this is possible and i also thought that if you model edit, its a universal change i.e. Undead to Gnome means all Undead's appear as Gnomes but this isnt the case in these movies.
The 2 movies in question are;
Tharbad's: Tharbad Frost Mage PvP
and
Agramon's: Agramon II

Any help would be appreciated. Thanks

[unreal]

its a debuff.

[Petey]

yeah, u can get it from the demension ripper area 52 for example. its just a engi thing.