Athar Null

If the null is subjected to an effect that allows it to make a saving throw to take half as much damage, it instead takes no damage if it succeeds on the saving throw, and half as much damage if it fails.

The null makes two Force Dagger attacks.

Melee or Ranged Weapon Attack +6 to hit, reach 5 ft. or range 20/60 ft., one target. 5 (1d4 + 3) Piercing damage plus 13 (3d8) Force damage.
The dagger magically returns to the null's hand immediately after a ranged attack.

The null takes the Dash, Disengage, or Use an Object action.

The null utters a magical word of cancellation to interrupt a creature it can see that is casting a spell. If the spell is 3rd level or lower, it fails and has no effect. If the spell is 4th level or higher, the null makes an Intelligence check (DC 10 + the spell's level). On a successful check, the spell fails and has no effect.