Haven't fought Kos yet. Assuming he's in the Fishing Hamlet? All I did was activate that lamp. Lady Maria was easy as hell to me. Beat her on either my 2nd or 3rd try. I'd rather fight 3 Marias or hell, 2 Ludwigs then Laurence by himself. Dude has my number, that's for sure.
I've noticed that if you get in close to him off to the side, he starts stomping around trying to get at you. It seems like you can just walk along with him while he's trying to get you without him actually hitting you (though you take damage from the little lava puddles he drops), but I always panic and either run (or roll for no reason, SMH) directly into his stomping. Of course I'm sure that's when he'll shyt out the huge lake of lava behind him if you do that for too long, but still. I seem to have a decent enough strategy for the 2nd stage, but it just never works out for me for some stupid reason. And of course I have to get to that stage, which I constantly have trouble doing. SMH, I hate that dude.