That can probably be done using data strings in the unit's name. You notice on spells the damage rate in the description is nothing more then a string, becasue the damage its self can be edited. There is probably a similar string that can be associated with player names. So in short, the object editor is probably your best bet, instead of triggers. -VGsatomi
use the spell Chaos, it instantly turns units into something else you specified. make chaos change one unit into a clone of itself, but with another name.