Mass Effect 4: What Happens After ME3's Destroy Ending

gamerant.com:

Fans are excited to see what is in store for Mass Effect 4, from its characters to its plot. Little has been revealed, but promotional materials have given everyone the idea that the new Mass Effect will have far more to do with the original trilogy than Mass Effect: Andromeda. The big question is, how will Mass Effect continue in the Milky Way between the various endings players chose?

Some players have been theorizing that BioWare may be continuing the series off of the Destroy Ending, and there is evidence for this. Concept art has shown a Systems Alliance Mass Relay, which may hint that the relays had to be rebuilt, and Liara walks over a dead Reaper. The Destroy Ending is the only one with the Reapers destroyed. Little is said of what happens after Shepard destroys the Reapers, but what is known and speculated may be important to prepare for Mass Effect 4.

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While the Destroy Ending eliminated the Reapers, it also destroyed the relays and all synthetic lifeforms, such as the geth and EDI. If the player has enough Galactic Readiness, Shepard is shown to have survived all the destruction. The Galactic Readiness actually affected more than Shepard's survival, but also the survival of people in general. If the Galactic Readiness was low, then far more than the Reapers are destroyed. Many people die in the red blast and many buildings fall.

After the blast in the extended cut DLC, a narration done by Admiral Hackett explains that the war is over. He confirms that the relays have been damaged, but the war has proven that the galaxy is strongest when all are working together. The speech is optimistic about the future, mentioning that if they can defeat the Reapers together,