Who wins?
Marathon vs Concord
Marathon wins 90% to 10%. 77 more put them in the same row. From Live Service Games Tier List. Pick a side.
tiny_nugget on Marathon: the october wipe actually fixed a lot, give it until the december PvE update
throwaway72569 on Concord: shut down two weeks after launch, easiest F ever
Live Service Games Tier List: the full ranking