You have advantage on saving throws against being knocked prone.

You have an additional set of arms, which end in large pincers. Your pincers are natural weapons, which you can use to make unarmed strikes. If you hit with them, you deal your choice of slashing or bludgeoning damage equal to 1d6 + your Strength modifier. These claws can't precisely manipulate anything and can't wield weapons, magic items, or other specialized equipment. Additionally you gain advantage on checks made to grapple or hold grapples with these pincers.

When you have a creature grappled with your pincers you can make an unarmed strike with the same claw you are grappling with. If you hit with it, you deal slashing or bludgeoning damage equal to 1d8 + your Strength modifier, instead of bludgeoning damage normal for an unarmed strike.

As a bonus action, you can emit dim light in a radius of 15 feet centered on you. You can end this effect as a bonus action. Once per day, you can cause the dim light to become bright light, no action required. This bright light lasts for one minute or until you end it as a bonus action. You count as being proficient with either Intimidation or Persuasion when this trait is active. This can't be changed later.

You have proficiency in the Perception skill. Additionally, your proficiency bonus is doubled for any ability check you make with the Perception skill.

You can perceive your surroundings without relying on sight, within a range of 30 feet.

You can breathe air and water and you have resistance to cold damage. And you are unaffected by extreme pressure made by being deep underwater.

You can see in dim light within 60 feet of you as if it were in bright light, and in darkness as if it were dim light. You can’t discern color in darkness, only shades of gray. As your vision is adapted for water, you can see the color blue at any depth.

You are a Monstrosity.

Decapodians usually stand at about 6-8 feet. Your size is Medium.

Not really made to live on land your base walking speed is 25 feet and a swimming speed of 30 feet.

You have a thick carapace you when aren't wearing armor, your AC is 12 + your Constitution modifier. You can use your natural armor to determine your AC if the armor you wear would leave you with a lower AC. A shield's benefits apply as normal while you use your natural armor.