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There's some division here:
Set Right What Once Went Wrong — They change something bad in the past to make a better present.
Set Wrong What Was Once Made Right — They change the past and (accidentally) make a worse present.
Butterfly of Doom — The concept of tiny changes to the past making unpredictable, possibly catastrophic changes to the present.
Juuuust in case there's any confusion, you are on Trope Finder where we find tropes, not works.
Edited by KD

about a time trveler who visits his past and changes his present