Self Exsanguination (3.5e Feat)
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Self Exsanguination [General]
Add even more blood to your spells!
When using your blood component ability, you may now sacrifice up to twice your Constitution modifier in hit points, gaining an increase in caster level as normal.
You may only raise your caster level to double your normal caster level when using your blood component ability.
For every 5 hit points you sacrifice, you take 1 point of Constitution damage.