Sanguine Soldier

School: transmutation [blood]
Level: sanguine sorcerer 4
Casting Time: 1 swift action
Components: V, S
Range: personal
Target: self
Duration: 1 round/level
Saving Throw: none
Spell Resistance: no
Description: You become affected by Sanguine Escalation and Sanguine Vulnerability. Additionally, you gain a stack of Bloodlust.
Note: You can possess no more than [x] stacks of Bloodlust at any given time.
[x] is equal to your caster level divided by two (rounded down)

Sanguine Escalation
Whenever a being (excluding yourself) takes damage from a bleed effect that you had inflicted upon them, you gain a stack of Bloodlust.
Hitpoint bleed effects that you inflict upon other beings deal escalating bleed damage.
Special: While you possess at least four stacks of Bloodlust, you gain the effects of the Bloody Vengeance feat (even if you do not meet its prerequisites).

Sanguine Vulnerability
Whenever you sacrifice hitpoints via Blood Magic or Crimson Concentration, you gain a stack of Bloodlust.
Whenever you deal hitpoint damage (excluding bleed damage) to another being(s), that being(s) becomes vulnerable to spells/abilities/etc. with the blood descriptor for [v] rounds.
[v] is equal to the number of stacks of Bloodlust that you possess