Drew Karpyshyn was the lead writer on the first two games in the Mass Effect series, but left BioWare before the trilogy ended with Mass Effect 3. Now, in a so-called Ask Me Anything on Reddit, the game writer tells us how the trilogy could have ended with him at the helm.
The ending of the third game was much debated at the time, and if you still have it unplayed, you'd better not read any further, because we're getting into spoiler-specific details.
As you know, Mass Effect 3 had a number of different endings, almost all of which resulted in the defeat of the invading Reapers. This also happened in Karpyshyn's version, although it was done in a slightly different way, as the Crucible superweapon was not used.
"As for Mass Effect, we had some very rough ideas planned out. Basically, it involved luring the Reapers through the Mass Relays then detonating the entire network to wipe them out... but also destroying/damaging the relays and isolating every galactic community from the others. But we still had to figure out a lot of the details, and there were some issues with that option... like what we would do in the next series of games."
The so-called Mass Relays, used for instant transport between distant galaxies, were also destroyed in some of the final stages of Mass Effect 3, so Karpyshyn's original vision wasn't abandoned entirely.
BioWare currently has a fifth Mass Effect in development. However, the game has yet to receive a launch window or, for that matter, even be shown off.