The Great Curse

You didn't find or choose your patron, it chose you. You are cursed and can be manipulated out of your will. If your patron feels that you're doing something they don't like, they can hurt you to their will. This subclass is very GM heavy as the GM needs to decide what happens and has to follow the ways of your backstory. 

This is the 1st version of this subclass so expect heavy change, I'm up for any constructive criticism. 

Crumbled Stance

Your appearance sends fear to those who look at you. Once per short rest, you can choose to look at a creature that is within 10 ft of you and can see you. The chosen creature must make a DC 10 + your constitution modifier Wisdom saving throw or have the Frightened condition for 1 hour at you. 

If the creature succeeds, you take 1d4 + the difference of your DC and what the creature rolled psychic damage.

Catching a Break

For a moment, you can control your will. You may roll a DC 15 Wisdom Saving throw, casting False Life on yourself at 1st level on succession, and dealing 1d8 necrotic damage upon failure.

This feature can be used 3 times per short rest.

Blood Tether

You create a deep red tether that shoots out of your chest like a sharp arrow through the back, connecting it to any creature in your line of sight, up to 30 ft. On use, you take 1d6 piercing damage. You and the creature take the same damage, the same conditions, etc., as long as the tether is connected. To disconnect the tether, the creature may roll a DC 12 + your constitution modifier strength or wisdom saving throw, or as a bonus action the tether can be dispelled. 

This feature can only be used per long rest.

Accursed Arachnid Legs

You've gained temporary mutation abilities. You may spend 1 action to sprawl up to 4 sets of arachnid legs from your back, dealing 1d6 piercing damage per set.
Each set of legs gives more speed, the lowest being a set of 2 legs, giving an additional 10 ft of walking speed. Each set stacks by 10 ft, making the maximum 40 ft. 

Additionally, you have the option to use one of the sets as an unarmed strike, having the same hit modifier as your normal modifier. Each hit deals 2d4 piercing damage.

This ability can only be used once per short rest.

Devour

You've gained the ability to rip your body apart to devour someone with piercing teeth in the opening. For 1 bonus action, you may rip yourself open using muscles you didn't know you had. Everything from your chest to your abdomen rips open, revealing a set of bloodied teeth and dealing 6d10 piercing damage. Anything the same size or smaller than you is devoured, dealing 6d12 piercing damage on contact. 
After use, you heal back to normal, the only thing showing change being the blood splattered on your chest. 

This can only be used once per short rest.