Mark of The Vendread

(Only one player can have this mark in a campaign.)

A unique birthmark granted to a bloodline cursed by death himself. 

Gain +1 to your spell save DC or a +2 to hit with any touch spell cast through the arm. Additionally, a cantrip may be stored in the arm and cast as a touch spell even if it was ranged. Cantrips stored this way gain bonus damage equal to your spellcasting modifier as necrotic damage and may be stored for up to a minimum of 1 day, up to your spellcasting modifier. This feature can be used up to a number of times equal to your proficiency bonus.

You may conjunct the stored cantrip with a touch spell attack, into a single attack action.