Blood Bridge

You draw out an enemy's life's blood equal to 2d8 + your spell casting modifier and use it to restore yourself. If you heal yourself completely and there is left over health, that is converted into temporary  hit points. The temporary HP lasts for one minute or until you transfer it to a willing ally.

When you cast this spell using a spell slot of 2nd level or higher, the damage increases by 1d8 for each slot level above 1st.