Vampiric Aura

This spell creates a 10' radius Aura around the caster marked by glowing Vampiric energy.  

Any enemy creatures that come within range for the first time or start there turn in the aura must make a Constitution saving throw.  Upon a fail, they receive 2d6 Necrotic damage.  The caster also heals for half of the damage dealt to the 1st target of the spell. on a successful save nothing happens

At higher levels.  The damage increases by 2d6 for every level above 1st, and you can absorb half the damage done from another target for every level above 1st.