Your Charisma score increases by 2, and two other ability scores of your choice increase by 1.

You are a distorted and horrific combination of two separate skeletons from two different races fused together by magic. You may have anywhere between one eye socket or four, your hands and feet may have a few extra digits or a few less that are larger than what seems practical. Your body is quite open and hallow giving you resistance to piercing damage. You may have some over calcified vertebrae with a few spines on them or extra bones merged on top of one another. You are also immune to poison on account of being a skeleton.

Your height is given by the tallest of the two skeletons that comprise your form and your weight should not exceed 100 lb. You are a small or medium-sized creature based on overall height.

You also don't need to eat, drink, sleep, or breathe. 

Your base walking speed is 30 feet.

Amalgamation Skeletons aren't typically made with free will in mind. Those that become sentient individuals typically stay with the lich who made them. The few who decide to seek more than servitude to their master lich find themselves hunted by their maker or any number of paladins and monster hunters seeking to rid the world of evil. Your alignment leans towards Chaotic Neutral.

Your unnatural features and disturbing visage granted by the necromancy that made you gain proficiency in the Intimidation skill.

 You can't be magically put to sleep.

You learn the Chill Touch and Antilife Shell cantrips due to being undead.

At level 1, the undead of CR 1/4 or lower within 100 ft. that can see or hear you become afraid of you and won't willingly attack you. At level 5, the undead of CR 1/2 will be affected by your aura. At level 10 undead of CR 1 will be affected, at level 15, the undead of CR 2 will be affected. At level 20, any undead of CR 4 or lower will be affected and will unquestionably follow any orders you give them.

When your HP is reduced to 0 you are completely aware of your surroundings but are unable to move or interact with them. When you succeed on a death saving throw you regain 1HP and are considered prone.

 If you kill any creature your size or larger, you gain a number of temporary hit points equal to your Constitution modifier. (Minimum of 1) Your temporary hit points last until you lose them in combat or take a long rest.

You can speak, read and write Common, Infernal, Abyssal, and the two languages that were known by the skeletons that your body is made of.

Thanks to you being undead, you have superior vision in dark and dim conditions. You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were dim light. You can’t discern color in darkness, only shades of gray.

You are immune to disease and treat exhaustion as if it was non-exsistent. Instead of sleeping, you enter an inactive state for 4 hours each day. you do not dream in this state; you are fully aware of your surroundings and notice approaching enemies and other events as normal.