Eldritch lineage 

When creating your eldritch abomination choose one humanoid race, This will now be know as your lineage.

You can also choose one racial trait from your lineages race, For example dark vision or infernal legacy from tiefling. 

When using these ability put a eldritch spin on them.

Ability Score Increase 

Use you lineages ability score increase, If it does not gain any you do not gain any.

 Demonic Screech 

As a bonus action, you can let out an echoing scream of madness filling creatures with dread. Every creatures within ally included 10 feet of you that can hear you must succeed on a Wisdom saving throw or become frightened of you until the end of your next turn. The DC of the save equals 8 + your proficiency bonus + your Constitution modifier. Once you use this trait, you can’t use it again until you finish a short or long rest.

Shape form

You may shift freely between two forms, An eldritch form and a humanoid form.

Eldritch form 

You shift from your humanoid form to your eldritch from.

While in your eldritch form you gain access to your eldritch appendages.

Humanoid form

Your humanoid form will look like that of your eldritch linage.

When in humanoid form you lose access to your eldritch appendages.

Hunger of the incomplete

You cannot eat normal food in any form, You must eat sentient humanoids souls.

Constitution of the eldritch

When you first create your eldritch horror roll 1d6 + CON for the amount of day you can survive without food for. Every level you may re-roll this stat and choose from either your old or new constitution.

Hunger of the eldritch

When you eat a creature you gain nourishment allowing you to survive for the rolled amount in the constitution of the eldritch.

When eating more than one creature it is not additive, it only resets the time in which you have till you need to eat again.

When the constitution of the eldritch time runs out you take 1 level of exhaustion per 1 day. 

When suffering from exhaustion from hunger of the eldritch you no longer lose speed, Instead you gain speed. Example : Exhaustion level 2 doubles your speed While 5 give you + 10 speed.

When in your eldritch form you gain these advantages.

At the start you gain 3 points and 1 point per level. You may spend these points to add an extra appendage to your body from the list below or talk with your dm about adding a different type of limb.

Arm

You may use you extra arm for basic tasks such as holding things or moving items, During combat you may attack using the arms as bonus action counting as an unarmed strike (Unless wielding a weapon in the limb) Dealing half the damage rounded down to a even number if holding anything.

Leg

You may attack using you legs such and a kick dealing unarmed damage knocking back the creature on a failed strength saving throw against a strength throw d20.

You may sacrifice all of your actions to get down on all legs and sprint and gain+5 movement per leg and doubling your moment speed, you cannot stop moving until you have used your full range of movement. If you move through a creature, deal 1d4 per leg and knock them prone of failed strength throw. This can hit multiple creatures but only hitting once per creature. This doesn't provoke opportunity of attack.

Tendril

Tendrils similar to arms, You may attack creatures dealing unarmed damage.

You may grab a target and grapple the target lifting them into the air, You may move or attack while the target if grappled at half your movement speed.

Eye

When you have extra eye add  +2 to your perception.

This caps out at +6 perception.