this staff grants you a +2 to your ranged spell attack and save DC when you hit with a spell attack you can spend a hit dice and have the target make a con save of 15 on a failed save the target gains a level of exhaustion and is drained for the amount of health you rolled on your hit die you gain temp HP equal to the number rolled you can sacrifice any number of hit die to copy this effect
 

(curse effect when a creature succeeds the con saving throw to be drained the staff still hungers and drains the wielder for the number rolled )  

Notes: Bonus: Magic, Bonus: Spell Attacks, binding your blood to the staff , Damage, Control, Detection, Combat, Deception, Warding