Pyromancy of Carmina, who harnessed the power of flame to actualize the inner-self. strength/endurance boost, but lose HP. Excessive power eats away the life-force of its caster, and like all dangerous spells, Power Within was kept secret for eons.Power Within is a buff spell from Dark Souls considered a member of the Pyromancy class of magic. It comes with the terrifying drawback that it can very well kill you if used. Today I will model this using Sorcery.
Statting and Combining the Components
Power Within Buff (-80%): (Mana Sensitive -10%; Costs 2 HP, Cyclic, 10 cycles, 10 Seconds -120%) 
Note that maximum limitation discount is limited to -80% even though we greatly exceeded that. Someone who might want to do some min-maxing might find some value to squeeze into the -50% that we don't have access to.