asylum is prob easiest on regular run (not ng+ but still easy) as long as you know the trick to killing him early
i never battled stray 4 some reason
taurus comes close, but the tight location could have you ending up off the ledge (just stick under him and jab away w/ resin)
bell gargoyles are hilarious w/ solaire, but a pain if solod (half health bringing in that annoying 180 fire breathing punk)
moonlight butterfly could be a little bit harsh due to its shotgun pattern, but npc summon usually handles it fine
sif requires a bit of patience and timing, as well as descent weapons and armor to take him down
quelaag is incredibly easy as long as you know what youre doing, shes really just a crash course for peeps-forcing them to learn attack patterns and practice timing. also to note she has a ton of health; npc summon will save you a ton of annoyance
iron golem- i never faced this guy w/o tarkus because of how hysterical it is to watch him solo on reg play (ng+ isnt really an option)
orny and smores was actually incredibly easy for me, but only because i had 2 summons (solaire + fatnom) otherwise they bring in the hurt
dark sun gwyndolyn or w/e wasnt 2 shabby, but no clipping walls was annoying
pinwheel is just a joke if you have a ludicrously powered up weapon (any weapon +5 or higher)
discharge is only easy due 2 1shot capability
but to even trigger that youre practically in a death race against his ridics aoe moves (horrifying on ng+ and beyond)
fire demon sage hardest for me, his aoe halberd slam covers 1/2 the room and he always did that to me 90% of the time
took me 15 tries to slaughter this punk
centipede demon wasnt all that bad, but lava kills quick
his grab and leap are menacing, but manageable
lord soul wise
bed of chaos might probably be considered the hard since its not even really a fight, but rather a luck mission of not getting hit
nito is only a pain due to the skeletons beforehand and his scream pillars lol
4kings werent fun due to the fight being based on speed, you could easily end up outnumbered and back @ a bonfire
seath was probs the easiest to me, sprinting past and taking care of the crystal and then having him trigger breath attacks while i hacked way @ his limbs
no comment on gwyn