With the wyvern dead there’s not much really to say about the rest of the peak. There’s a bunch more of those tough dragon-snake-men as well as some dragon-snake-priests that can summon powerful human heroes to fight you (most of which drop unique items the first time you kill them). You can also find a titanite slab and a warrior wearing the super-heavy Havel armor set. Killing him doesn’t earn you the armor but it does cause a random corpse in an unrelated area to spawn with the set as loot (no idea how you’re supposed to figure that out without a guide).
I suppose there’s also a super-duper-mega-ultra bonus boss here but Fault is just going to ignore him, possibly forever. Discretion is the better part of valor and all that.
Even if you ignore the bonus boss you can still fight your way all the way to the top of the peak where you’ll find an alter overlooking what seems to be a giant petrified dragon the size of a mountain. Meditating there earns you a special dragon stone that lets you transform your torso into a sort of dragon-hybrid form if you aren’t wearing any armor. I guess it’s cool if you’re into that (Fault’s prefers her armor).
But you know who is into that? That depressed knight that’s been hanging around the Firelink shrine all game. Return to home base with the dragon stone and the blacksmith will mention that the depressed knight wants to meet up with you in one of the old boss arenas. As soon as you show up the knight mentions something about how the path of the dragon only allows for one disciple at a time at which point he murderers you and steals your dragon stone.
Now the funny thing here is that he had just asked for the thing or maybe offered to trade his socks or some other random item for it Fault would have gladly accepted like the side-quest hungry RPG protagonist she is. But he just had to go and introduce murder into the mix and Fault is now dedicated to respawing again and again until she has her revenge. At which point, having earned a complete set of dragon artifacts, she promptly gets on with her life and never thinks about the way of the dragon again.
Anyways, now seems like a good time to go and refight Prince Lothric’s brother and after a few more deaths than I’d like to admit Fault finally emerges victorious.
Ok, now I must really have all the Lords of Cinder. The thrones are all full and everything. That means it’s time for the final boss!