Beautifully broken: Right hand Irithyll straight sword, left hand Fire or Chaos infused curved sword or rapier (pyro flame combustion works, and fire surge is just perfect).
2 hits with the frost (slashing hits seem to do more frost, you'll need 3 with thrust)
those 2 hits will always proc frostbite for good damage, without any titanite investment on the sword
then l1 to use the curved sword
Just get into a rhythm - dodge attack, if he has lag, r1 r1 l1 or l1 r1 r1
Whichever you prefer
Either way, you kill him fast. I kinda like l1 r1 r1 more (Fire, ice, ice), as he seems more docile when he's frostbitten.
It also seems as though hitting him with fire damage doesn't remove frost Buildup, just the status effect
So if I do a rolling attack and a slashing attack (not quite enough for a frostbite proc), and then hit with fire, frostbite will proc on the next ice attack.
I feel (and I'm an idiot, so whatever) like a pyro could use this in pvp. Pyro flame, ice weapon. If you deal most of your damage with pyro, but brawl up-close with ice, it seems like you end up with 2 ways to kill your opponent - catch 'em with flames, or proc the frostbite. Cud b gud