"Glass Cannon," meaning powerful attack but no defense. This style fuses the strength of a warrior with the magical finesse of a Sorcerer. The build will deal a lot of damage, but be warned, it cannot take too much.
Smelter Sword, Pyromancy Flame, Staff of Wisdom, no shield
Black Set, Hexer's Hood, Third Dragon Ring, Ring of Thorns +1, Ring of Binding, Brass Knuckle Ring
Soul Geyser, Crystal Soulmass, Soul Spear, Flame Swathe, Soul Greatsword, Firestorm/Fire Tempest or Crystal Soul Spear(NG+ only)
Work your first playthrough building specifically on FTH, INT and Attunement. Build just enough Strength and Dexterity to use a broadsword, just in case for those close encounters. The second playthrough can be used to level your strength for use of the Smelter Demon's Sword.