Does anyone know of any fics with competitive dueling, as in detailed tournaments or defined magic such as in Lung's The Wizard of the Kaleidoscope?

 

JBern's The Lie I've Lived has some detailed dueling sequences.

 

I don't know about "competitive dueling", but there's a whole thread with the best live action duels:

https://forums.darklordpotter.net/showthread.php?t=21285

Knock yourself out.

 

You can try The Point of Divergence. It has Harry going into professional dueling, but the story never got far.

 

Thanks Nargles, that looks more like the type of fic I am looking for. I already read The Lie That I've Lived, and it was a pretty good story despite not being what I am looking for.

 

Harry Potter and the Final Straw - there's a dueling tournament in the middle of the fanfic.
https://www.fanfiction.net/s/2159217/1/Harry-Potter-and-the-Final-Straw

 

The Birth of Evil by DisobedienceWriter features a proper Hogwarts duelling club and fully realised professional duelling competitions worldwide, with both Harry and Professor Flitwick taking part in both.

Link: https://www.fanfiction.net/s/4133028/1/The-Birth-of-Evil

 

Seize the Fire - https://www.fanfiction.net/s/9102184/1/Seize-the-Fire