Precursors.
Time Lords.
Forerunners.
Vex (Vault of Glass variants as they can delete you by rewriting what happened earlier).
...Any other indestructible, OP species?
Maybe Reapers (Reaper Indoctrination).
English
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Lol forerunners and precursors could both solo the reapers
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Yet Reapers have indoctrination, and might end up being 'hacked' by The Domain via that, making Reapers 'super-tools' for Precursors, practical 'avatars'.
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Daleks?
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Maybe.