Troll Fight

Any boss battle in a video game that takes an unnecessary about of time to complete without changing or evolving in any way to keep it interesting for that player. Created in indie horror YouTuber @itspeepohere's live chat as a result of the multiple El Gigante fights in Resident Evil 4 (2005)
It is a play on "troll" (the term for someone online who's only purpose is to antagonize others) and the fact that El Gigantes look like cave trolls.

"Are you gonna play Dark Souls?"
"I don't know. I heard it's nothing but troll fights. Dodging and slashing over and over for an hour sounds annoying."