There are vids of people beating them at sl1 on NG+7. They use R. Tearstone but they are also using an elemental weapon.
Link for those too lazy to search it out? XD
But in all seriousness, on NG+ cycles the Four Kings are a DPS race. It is the only fight in the game like that, where smart play alone isn't enough. You can still beat them with a weak weapon, but you need to get lucky several times when they're juggling you in a 3v1 fight.
"I'd rather betray the world than let the world betray me." -Cao Cao
My sl 5 dark beaded them to dead on ng+++, my sl 1 had a bit more trouble with the reinforce club and great combustion on ng+ but still prevaled. So you must have never played this game. That explains it.
I know this is just me but, Four Kings was done in one try (and in my head I saw it as a trial to see how hard Four Kings really was) on my first playthrough however I had good equipment and good stats. Got my ass kicked on second, but finally figured out an effective way of taking them out..From then on Four Kings never game me that much trouble. I'm on NG++++ now. No boss in the base game gives me any true trouble anymore except for Gwyn..It's not that he's hard, it's the fact that he paces the whole fight, because he really makes the fight intense.. Four Kings is a battle of DPS. I have to be very cautious fighting Gwyn even with the best spells in the game.
All the DLC bosses are hard, but I've only done it once as I got the DLC very recently.
If From ever does a boss like the Kings again, they need to make them less polite. When you're fighting one, the others tend to just sit back and chill when they should be launching magic and poking at you.
So they're tough, but I wish they were even tougher when you allowed more than one to spawn.