Scion of the Fiend

Your innate magic comes from the Lower Planes, and manifests in destructive ways.  Many tiefling sorcerers are of this subclass due to their infernal heritage.  You might have a fiendish ancestor, been corrupted by the dark power of the Abyss, or marked by a devil.  While you are not innately evil, many fiendish sorcerers end up there.

Fiendish Spells

You learn additional spells when you reach certain levels in this class, as shown on the Fiendish Spells table.  Each of these spells counts as a sorcerer spell for you, but doesn't count against the number of spells you know.

Whenever you gain a sorcerer level, you can replace one spell you gained from this feature with another spell of the same level.  The new spell must be a conjuration or evocation spell from the sorcerer, warlock, or wizard spell list.  The evocation spell must deal acid, cold, fire, necrotic, or poison damage.

Fiendish Spells

Sorcerer Level	Spells
1st	command, hellish rebuke, thaumaturgy
3rd	ray of enfeeblement, scorching ray
5th	bestow curse, magic circle
7th	fire shield, wall of fire
9th	flame strike, planar binding

Fiendish Channel

You can channel dark magic of the Lower Planes to alter fate.  When you make an attack roll, ability check, or saving throw, you can add 2d4 to the roll.  You can do so before or after you see the roll, but before the DM tells you the outcome.  Once you use this feature, you can't do so again until you finish a short or long rest.  Once you have sorcery points, you can spend 2 sorcery points to use this feature again.

Fiendish Resistance

You have resistance to cold, fire, or poison damage (your choice).

Summoner of Fiends

By 14th level, you are adept at calling on creatures of the Lower Planes.  You are learn the find familiar spell, which count as a sorcerer spell for you and doesn't count against the number of spells you know.  If you cast this spell using a spell slot of 5th level or higher, you can cause the familiar to be a fiend of CR 1 or lower, such as an imp or quasit.  The max CR for the familiar summoned increases by 1 for every two slot levels above 5th.  When the familiar is summoned in this way, it is able to attack once per turn.  Its hit points equal your Charisma modifier plus half your sorcerer level, rather than its normal hit points.  If your familiar is reduced to 0 hit points, you suffer the effects of the attack, spell, or other effect that reduced the fiend to 0 hit points, and you can't summon another fiend with find familiar for another 1d6 x 3 days.

Aura of Dread

Beginning at 18th level, you can fill creatures with dread invoked by the Lower Planes.  As an action, you can draw on this power and exude an aura of fear with a radius of 30 feet. For 1 minute or until you lose your concentration (as if you were casting a concentration spell), each hostile creature that is not native to the Lower Planes that starts its turn in this aura must succeed on a Wisdom saving throw or be frightened until the aura ends. A creature frightened by this aura has has disadvantage on attack rolls, saving throws, and ability checks until the effect ends.  A creature that is frightened by the aura can repeat the saving throw at the end of each of its turns, ending the effect on a success.  A creature that succeeds on this saving throw is immune to your aura for 24 hours.

Once you use this feature, you can't use it again until you finish a long rest or you spend 5 sorcery points to use it again.