What sort of playthrough are you doing???? Lol, please explain in dummy details
Are you making your self overpowered to get these 1 hits but sacrificing your health and endurance?
Hmmm, am I making myself owerpowered? That's a yes and no answer. I'll explain.
My current challenge was posted on YouTube by Vageta311, and it's a low-level, one shot boss challenge. The aim of the challenge is to earn points you can use to level yourself up, by killing main bosses in 2 hits or less (you earn 2 points for a one hit kill, and 1 point for a 2 hit kill), and by killing mini bosses in one hit. If you can't defeat any given main boss in less than 2 hits (or 3 hits if you're facing the Belfry Gargoyles, Orn and Smough, or Four Kings), then the challenge ends.
In practise, this means that before you can level up even once, you have to be able to kill at least one boss or mini boss in one hit. The only way to do this is by utilising some of the shortcuts (such as going via New Londo Ruins, to Valley of the Drakes, to Darkroot Basin, to Andre the Blacksmith) in the game to get your equipment and pyromancy levelled up as much as you can (as there is simply no way to defeat any of the early bosses without upgrading your equipment).
The trouble with the challenge is that you're always limited on how much you can level up, so you can't simply grind for souls then get to SL120 before blowing through the game. You have to plan ahead, know where and how to upgrade your equipment, and know how you want to level yourself up. I'm currently SL55 in my playthrough (with enough points spare to level up to SL64), and the only stats I've increased are Attunement, Strength, and Intelligence. I've still got base level Vitality and Endurance as I don't want to "waste" points on those stats, as they don't help me output more damage.
At this point in the game I really feel like a glass cannon. I can output tons of damage by using various buffs (Red Tearstone Ring, Power Within, Crown of Dusk, Dragon Torso Stone, etc), but I can rarely take more than one hit. It's made me very good at dodge rolling, riposting, and generally not taking much damage at all.
It's a fun challenge but it's certainly not for everyone. I've had to do at least 10 hours worth of farming in the game, which was really boring. I've grinded for souls, for upgrade materials, and for Dragon Scales, and there were times when I wanted to just end the challenge. It was all worth it though for the feeling I get when I take out someone like Knight Artorias or OnS in one hit.
Hope that explains the challenge enough. I've been recording my efforts and will be uploading to YouTube at some point I think, but if anyone wants to see a particular kill I can upload it separately.