Doomsayer

Any fool can learn to hurl a fireball, but only a master of the apocalypse can open a black hole. Wizards who specialize in such apocalyptic magic call themselves doomsayers. Some doomsayers use their terrible power to amass a conquering army; others seek to become a force of darkness and to reshape the world according to their own vision.

Doom Savant

Beginning when you select this specialty at 2nd level, the gold and time you must spend to copy a spell that is part of the doom style of magic (see Chapter 2) into your spellbook is halved.
 

Wicked Presence

At 2nd level, you gain the ability to instill a sense of impending doom in creatures who witness your power. When a spell you cast of 1st level or higher reduces a creature to 0 hit points, you can use a bonus action to terrify those nearby. Choose a number of creatures within 30 feet of that creature equal to your proficiency bonus. Each target must succeed on a Wisdom saving throw against your spell save DC or become frightened of you for 1 minute. A frightened creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. Once you use this feature, you can’t use it again until you finish a short or long rest.
 

Terrible Power

Starting at 6th level, your critical hits with spells have reverberating effects on their victims. Whenever you score a critical hit with a spell attack, choose one of the following effects for each target of the spell attack:

The target must succeed on a Wisdom saving throw against your spell save DC or become frightened of you until the end of its next turn.

The target must succeed on a Constitution saving throw against your spell save DC or become poisoned until the end of its next turn.

 

Merciless Onslaught

Starting at 10th level, you have advantage on spell attack rolls against creatures that are frightened or poisoned.
 

Power from Darkness

At 14th level, your spell attacks score a critical hit on a roll of 19 or 20.