Blood Memory

Blood Memory (Anti-Magic Shield): You learn to deflect certain automatic hits with necromantic energy. As a reaction, when you are targeted by Magic Missile or a similar effect that hits without an attack roll you can surround yourself with a dark aegis of necrotic power. This negates the incoming Magic Missile spell completely, preventing all damage from it, and grants you resistance to force damage until the start of your next turn. You can use this feature once per long rest at 2nd level.

At higher levels: 
10th level, you can use Blood Echo twice per long rest.

15th level, your mastery of this defense is such that Magic Missile and similar “auto-hit” minor spells no longer affect you at all (you passively ignore them), and you permanently have resistance to force damage. (By high levels, lesser magical projectiles are almost futile against you.) This ability reflects your unique undead defense—few classes can foil Magic Missile without casting Shield, making you uniquely suited to counter certain magical attacks.