While dragons are most famously associated with those sorcerers for whom draconic power flows through their very blood, a part of who they are, they are not the only ones who envy the power of wyrms. Some are raised in cults that worship powerful dragons as gods, others enter into sworn service to a dragon master, and still others try to steal away a dragon's most precious and jealously guarded treasure: their own power. All these and more are dragonsworn warlocks, wielding the power of dragons in mortal hands.
When you select this archetype at 1st level, you gain a boon of draconic power. Choose a damage type as your draconic damage type: fire, cold, lightning, acid, or poison. Once chosen this cannot be changed. Select one of the following:
You can use a bonus action to curse a creature within 30 feet. The curse lasts for 1 minute, and ends early if the target dies, you die, or you become incapacitated. The curse has the following effects:
Once you have used this ability, you cannot use it again until you finish a short or long rest.
You may use an action to breath out a 15 foot cone or 5 foot wide 30 long foot line. You choose the shape of this breath when you gain this ability and cannot change it. Creatures in the area must make a Dexterity saving throw against your warlock spell save DC or take 2d6 damage of your draconic damage type on a failure or half damage on a success. If your draconic damage type is cold or poison, they must instead make a Constitution saving throw. This damage increases by 1d6 at 10th level, and again at 15th and 20th level. At 14th level the area increases to a 30 foot cone or a 5 foot wide, 60 foot long line. You can use this attack a number of times equal to your proficiency bonus and regain all expended uses when you finish a short or long rest.
At 6th level you gain resistance to your draconic damage type. In addition, whenever you fail a saving throw, you can use your reaction to roll a d4 and add it to the result of the saving throw, potentially turning it into a success. You can do so a number of times equal to your proficiency bonus and regain all expended uses when you finish a short or long rest.
At 10th level as an action, you let out a supernaturally loud roar infused with dragonfear. You can force all creatures of your choice within 60 feet to make a Charisma saving throw against your warlock spell save DC. On a failure they are frightened of you for 1 minute. Frightened creatures may repeat the save at the end of each of their turns, ending the effect on itself on a success. This counts as a dragon's fear ability for the Draconic Curse ability. Once you have used this ability, you cannot do so again until you finish a short or long rest.
At 14th level, you gain the services of a draconic mount, either an ally you have bonded, a gift from your master, or a creature you have broken and bound to you. You may cast the find steed spell at 5th level without expending spell points once per long rest. The steed you summon always has the stats of a giant lizard with the following changes: it is large, has an AC of 18, it is immune to your draconic damage type, you must choose to give it a fly speed instead of a swim speed, its type is dragon, it uses your spell attack bonus for any attacks it makes, and it gains a breath weapon action. This breath weapon is a 30 foot cone and deals 5d6 damage your draconic damage type on a failure or half damage on a success, uses your warlock spell save DC, and can only be used once per short or long rest.