Questions about finishing my first game

[ConfusedDm]

I started playing dnd a couple months back and i started off as a kight homebrew class bc it was actually kinda balanced but it was changed to something in my opinion broken so i was playing a half dragon and i decided i would go in to becoming a cleric of the dragon god of fire not know my character would kinda go insane in the process and i was totally fine with at first but now my dm wants me to be the bbeg and i was totally on board with it and now i cant decide if i should let my friends win or if i should kill them and that's how we end our game. Please would love some help

[Aegis013]

If you're not on board with becoming the villain, talk to your DM Out-of-character and let him know. Try not to be accusatory, just informative. See if you can come up with another interesting alternative together that would be more fun for you.

[ConfusedDm]

If you're not on board with becoming the villain, talk to your DM Out-of-character and let him know. Try not to be accusatory, just informative. See if you can come up with another interesting alternative together that would be more fun for you.

The problem isnt that i dont want to be the bad guy its that im trying to decide if i should let my friends win the final fight by making it hard for them but they still win type thing or if i should just try my hardest to do a TPK but i dont want them to think that dnd is a competitive game with that but thanks for the advice