>>69671777Yeah there's a second monkey fight.
The game is set up in a weird way, during the middle section there are 3 parallel paths that you can do in any order. The 1st Monkey fight is on one of these routes, but beating it puts the 2nd Monkey fight on one of the other routes. If you do that other route first, you skip the 2nd monkey entirely, but if you do 1st monkey beforehand then 2nd monkey becomes mandatory. If you're unlucky you can end up doing both monkey fights back to back with literally no other content in between.
The 2nd Monkey fight gives you the best ninja skill in the game so it's absolutely worthwhile but it can be kind of shitty spending hours on monkey only to immediately be progression-walled by the same fucking fight again.