I saved the Rachni in ME1, so now in ME3 I have to kill them on a frequent basis.
I'm just wondering, what would happen if I would have killed them? Would they still be there, or replaced by another ennemy? Also, if they are still there, what is the explanation why this species you made extinct yourself in still running around?
For those who wouldn't know what a rachni look like, Heres what it looks like.
And I'm fighting them
Right in the Ancient City of the Krogan, on Tuchanka.
Best Answer
It actually seems saving the Queen in ME1 and then again in 3, will be more beneficial to Shepard.
As with all "plot" characters that die, they do get some form of replacement, it just so happens her replacement is much more sinister.
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Personally, I saved the Queen, which, losing the Krogans sucked ('cept for Grunt's general awesomeness), provided a ton of War Assets added to the cause.