User blog comment:SanjayBeast/Anyone else pissed about lack of Protheans in MP?/@comment-5156224-20120601190254/@comment-4491632-20120601191841

Basically this. You'd have to do some serious lore retcon to fit the protheans into the multiplayer.

And Blasto... xD While he would be hilarious, the hanar have very little combat potential. Would probably be more confusing than trying to fit the protheans into the multiplayer modes.