You may call upon the souls of any humanoid who has died within the last 15 minutes that is within range (you can increase this range by 5 ft. for every extra 1 minute spent casting with a max of 20 ft) . By doing so, you prevent them from traveling to their afterlife. Instead the soul is captured within your body giving you temporary hit points equal to your spell caster level/2 and rounded up. You may choose to free a soul at will if they can no longer provide you with temporary hit points.
If your hit points drop below zero while there are souls captured within you or the number of souls exceed your spell casting level, then the spirits release from your body in an explosion of force. You lose all temporary hit points and everyone around you is dealt 1d4 force damage for every soul inside of you in a 5ft radius.
At Higher Levels. When you cast this spell using a spell slot of 2rd level or higher, the casting time decreases by 1 minute for each slot level above 1st.
* - (Must use an Arcane Focus)