Callum, the False Prophet

Impossible Portents (1/Day). At the end of a Long Rest, Callum rolls two d20s and records the results. Before a creature Callum can see makes an attack roll, saving throw, or ability check, Callum may replace the roll with one of these recorded results. When he does, purple-blue runes briefly spiral around the target as reality subtly rearranges itself.
"I've already seen this part."

Metamagic Adept. Twice per round, Callum may apply one of the following effects to a spell he casts:

• Quickened Spell
  A spell with a casting time of 1 Action becomes a Bonus Action.
• Subtle Spell
  The spell requires no verbal or somatic components. Magic simply manifests around him instinctively.
  "Most wizards are very dramatic about all this."

Timeline Anomaly. Callum has Advantage on saving throws against spells and magical effects. Additionally, he cannot be unwillingly teleported or banished. Reality struggles to decide where—and when—he properly belongs.

Multiattack. Callum can cast 1 leveled spell, 1 Overwhelming Revelation, or 2 Spellfire Bursts

Spellfire Burst. Melee or Ranged Spell Attack: +9 to hit, reach 5 ft. or range 120 ft., one target. Hit: 20 (3d10 + 4) radiant damage. The blast resembles concentrated stellar fire wrapped in fragmented arcane equations.
"Okay, THAT one was intentional."

Overwhelming Revelation (Recharge 5–6). Callum magically creates a burst of illumination in a 10-foot-radius sphere centered on a point within 120 feet of it. Each creature in that area must make a DC 15 Wisdom saving throw. On a failed save, a creature takes 45 (10d8) psychic damage and is stunned until the end of the Callum's next turn. On a successful save, the creature takes half as much damage and isn’t stunned.

Spellcasting. Callum's is a 9th level spell caster and uses his Intelligence as his casting for his magic, his spell attack is +9 (spell save DC 17):

At will: Fire Bolt, Mage Hand, Message, Prestidigitation

3/day each: Arcane Eye, Dispel Magic, Shield, Misty Step, Lightning Bolt, Counterspell, Fireball, Rary’s telepathic bond

2/day each: Fly, Haste, Detect Magic, Hypnotic Pattern

1/day: True Seeing, Wall of Force, Cone of Cold

Fractured Probability (2/Day). Callum destabilizes causality around a creature he can see within 60 feet. The target must make a DC 17 Intelligence saving throw. On a failure target takes 31 (7d8) Psychic damage, cannot take Reactions and si moved to any location Callum can see within 60ft. On a success target takes half damage.
The target experiences contradictory versions of reality simultaneously.
"Your problem is you're only experiencing one timeline."

Retroactive Correction. When Callum or a creature within 30 feet takes damage, Callum twists local causality. Reduce the damage by 18 (4d8). Reality visibly skips backward for half a second.
"No, no, let's try that differently."

Son of the Paradox (1/Day). Callum fully unleashes the impossible interaction between Spellfire and his existence outside the proper timeline. Callum can keep this going for every round as it consumes spellslots (Max of five rounds for five-3rd lvled spellslots)

Reality Collapse. At the start of each of Callum's turns while the ability is active, creatures of his choice within 30 feet must make a DC 17 Dexterity saving throw. On a failure target takes 18 (4d8) Force damage and are pulled up to 15 feet toward a point of Callum's choice within the area.

On a Success target takes half damage as the battlefield bends inward around him like a dying star.

Spellfire Ascension. If Callum is reduced to half health while this ability is active, Callum gains the following: Flying Speed 40 ft. and Resistance to all damage except Psychic. 
After the ability ends (5 rounds max) at the start of Callum's turn he then gains:
2 levels of Exhaustion and Vulnerability to all damage until completing a Long Rest as arcane fractures remain burned into the environment for hours afterward.
"I don't think reality likes me very much."