Kumo Form

You have the ability to partially transform your body into a more monstrous form. As a bonus action, you can expend 15 Seiki points and enter your Kumo Form, gaining some of the physical traits of a Jorogumo. Your skin changes into a deathly gray color. Your sclera turn black, and your irises turn a sickly yellow. Two pairs of smaller eyes with no pupils or irises appear on your forehead. 4 spider legs grow from your back, your limbs become more lithe, and your nails sharpen into claws. Your jaw and mouth morphs in such away that allows you open your mouth wider than humans, while your teeth turn sharpen into fangs, and a pair of mandibles grow on either side of your mouth.

While in your Kumo Form you gain the following traits:

You gain darkvision up to 120ft.

You gain blindsight up to 30ft.

You gain tremorsense up to 20ft.

You can use the Dash and Disengage actions as bonus actions.

You are perpetually under the effects of the Jump spell.

Your movement speed doubles.

You gain a climbing speed equal to your movement speed.

You gain advantage on Wisdom (Perception) checks.

You become resistant to nonmagical damage, and immune to poison damage.

You are able to cast your Jorogumo spells without expending Seiki points.

You gain advantage on Dexterity and Constitution saving throws.

You gain magical resistance, granting you advantage on saving throws done to resist the effects of magic.

Your Strength, Dexterity, and Constitution scores increase to 18 if they weren't already 18 to begin with.

Additionally you gain the following actions:
Frightful Presence. When you first transform, or when a creature sees your for the first time in combat, each creature that is within 120 feet of you and is aware of you must succeed on a DC 16 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the Effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to your Frightful Presence for the next 24 hours.

Multiattack. You can make two attacks with your Spider Leg Swipe, or one Spider Leg Swipe and One Mandible Bite.

Mandible Bite. You can make a melee attack roll to try and bite a creature. On a hit the creature takes 2d6 + your Strength modifier magical piercing damage, plus an additional 1d8 poison damage. Once bitten, the creature must make a DC 16 Constitution saving throw or become poisoned. The creature can repeat the saving throw at the end of each of its turns, ending the Effect on itself on a success. While the creature is poisoned in this way, it takes 1d6 poison damage until the effect ends. If the effect ends for it, the creature is immune to your to this poisoned effect for 24 hours.
Additionally, you regain Seiki points equal to half the damage dealt by this attack. 

Spider Leg Swipe. You can make a melee attack roll, swiping you spider legs at a creature up 10ft away from you. On a hit, the creature takes 3d6 + your Strength modifier magical slashing damage.

This form ends after one minute or if you become unconscious. You can end the form early as a bonus action on your turn. Once you use this ability you gain 1 level of exhaustion and can't use this ability again until you finish a long rest.