here is an extract from a manga that gives me troubles : (|| = column breaks in the manga)
First : can you confirm that there are 2 different sentences :
However, I will be your only opponent. (???)
We wll fight one vs one and, if I win, the next person will fight with me again....
And that 闘い is equivalent to 闘って there? (Which sounds weird to me because I learned that it had a litterary use only and the character is speaking informally the rest of the time, using だ instead of です, 楽しませてくれ, instead ot 楽しませてください and so on...)
Assuming I'm right until there, I don't get what the first sentence means (especially why いい is used instead of a simple 私一人だ, but I found a lot of 私一人でいい occurences on google so...)。
Or I'm wrong and で is the てform of だ and いい modifies 一対一で, and I don't understand it either : Fight a good one vs one?)
Or, (thinking while writing), I'm wrong again and 闘い is just a noun and not the equivalent of 闘って and there is an を particle ommited after 闘い and いい modifies 一対一で闘い and then :
However, I will be your only opponent, and
If I win a good one on one fight,
The next person will fight with me again...