In mass effect they dont have very many races comparably!
and we have seen the vast majority
but there are indications of other races
nihilus says that some races in the terminus systems would be willing to go to war
some races? thatstatement implies that some races would and others wouldnt, so far we only know three terminus species, vorcha, batarian, and lystheni. We know nothing of the lytheni and the vorcha dont seem to be in a position to go to war.
So it stands to reason there are some races in the terminus systems that are active that we have yet to see
we also know of the raloi, the newest race to enter galactic civilization, good for them, i hope we see more of them.
And the females of many races are seemingly absent, female turians, drell, batarians, and volus (i'm sure theres more) lets hope to see more of these in the future.
so theres plenty of people we havent seen yet!
but i suggest that we may have seen one already go read mass effect incursion
look closely on the first page
WHAT THE HELL IS THAT either the artist had never seen a turian before EVER (and as indicated by later pages he has drawn turians a little mroe accuratly (page 4) and the fact that its the same artist that did redemption HE DEFINITLY HAS) and even right below that one
could this be the . . . . .lystheni, certainly they resemble turians in a greater capacity. But that could be the thing about lystheni, perhaps they spliced their own dna to extend their lives.
or the art could be wonky
i would prefer that they retcon it into a new sepcies though