Eat Soul

As a spell touch attack, eat the soul of your opponent. 

When you cast this spell, the target must make a CON 15 save or have their soul devoured. 

When you eat a soul:

Your HP is restored by an amount equal to the target's current hp. If this brings you above your max hp, add the rest as temp hp. 

You gain one ability point and may apply it to whichever ability score you want to a maximum of 30. 

You gain a free class level of the target (If they have one). This does not count as a level in relation to leveling up, so you could be level 20 and still gain this extra level.

(This is a meme spell. Not to be taken seriously, just for fun.)