Where were they supposed to have came from? They were created by the leviathans? They made an AI that eventually formed one in their likeness to solve a "problem" Then why in ME1 when you talk to Sovereign he says they are infinite and have no beginning. Why lie? Especially when its so sure the galaxy is done for.
-If we take the story at its word, it went like this:
Leviathans evolved into great power and came to rule the galaxy, spreading influence everywhere but mostly through the orbs (short range).
Organics still kept ending up creating synthetics and warring with them.
Leviathans in their arrogance make their own intelligence in order to find a solution to this recurring problem.
The intelligence determined that all organics were the problem, but instead of only eliminating them, it had to 'save' them, as that was what it was created to do. It used 'an army of pawns' (whether that means indoctrination or not) to strike against the Leviathans, harvest them, and create the first Reaper, Harbinger.
Over the Cycles, this process was perfected. Each Reaper contributed to the knowledge and process of the intelligence, and the galaxy became a grand experiment to solve the seemingly unsolvable.
As the Reapers contributed to the intelligence, the intelligence controlled the Reapers. This seemed to make a rather nihilistic loop where the harvest cycle was seen to be inevitable and part of the necessary process to bring synthetic order to organic chaos in the galaxy, or else organic races would be doomed to full-death by other organic-synthetic conflict.
-Sovereign was a character made before this whole deal was decided on. When it comes to the 'have no beginning, have no end, etc' stuff, there's a few possibilities, whether popular or my own thoughts:
1)He was just trash talking. As far as the organics of this cycle may be considered, the Reapers really do have no beginning or end. As in they lived before this Cycle did, and they'll endure after this Cycle is harvested.
2)The idea has been floated around, even seemingly by Mass Effect writers themselves, that the Reapers are the uploaded consciousness of the harvested species. With how we see synthetic consciousness in the trilogy, it isn't hard to imagine that there could be whole worlds, universes within Reapers. Maybe these worlds, and thus the Reaper consciousness, has 'no beginning and no end'. Maybe it loops. Sadly, we see very little that directly supports this being the case.
3)Something else entirely. Maybe something that the next game addresses. I dunno.
I heard there was a leak of the original ending of ME3. Is that true? If so was it a good ending and was then changed because of the leak? What was the ending and was the origin of reapers changed?
-Wasn't changed by very much.