Your Charisma score increases by 2, and your Strength score increases by 1.

Yuan-ti mature at the same rate as humans and have lifespans similar in length to theirs.

Abominations are animalistic and usually follow their base instincts and desires. They can be neutral but more often stray toward chaotic or evil alignments.

Abominations have torsoes and heads comparable in size to other tall humanoids, but their long snake-like lower halves can range anywhere from 8 to 20 ft. in length when straightened out. By propping yourself up with your tail, you can reach up to 8 or 9 feet above the ground at your full height.

Your size is Large, and your long tail gives you the following unique qualities:

• Any climb that requires hands and feet is slightly more difficult for you. When you make such a climb, each foot of movement costs you 2 extra feet, instead of the normal 1 extra foot.
• You count as one size smaller when determining the weight you can push, drag, or lift.

Your base walking speed is 30 feet.

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 poison damage and the poisoned condition.

Your powerful tail is incredibly useful for grappling. Whenever you attempt to a grapple a target, you can choose to use your tail instead of one of your other appendages, with the following changes applied:

• If you succeed on the initial grapple check by 5 or more, the target is also restrained while this grapple lasts. A target restrained by your tail enters your space and stays there until the grapple ends, at which point it emerges into an unoccupied space within 5 feet of you.
• While grappling with your tail, you are also considered grappled.
• While grappling with your tail, you can use a bonus action to constrict the grappled target and deal bludgeoning damage to it equal to 1d6 + your Strength modifier.

As an action, you can cast polymorph on yourself to turn into either a constrictor snake or a giant poisonous snake. Whenever you cast the spell with this feature, your snake form is always considered Large. After you cast the spell with this feature, you can't do so again until you complete a long rest.

You can speak, read, and write Common, Abyssal, and Draconic.