Amphibian
Amphibians are small and adaptable coldblooded animals. These include frogs, newts, salamanders, and toads. Amphibians are all about change, baby. Most amphibians have some ability to resist poison, and all are aquatic at some point in their life cycle.
Ability Score Increase: When determining your character’s ability scores, increase one score by 2 and increase a different score by 1, or increase three different scores by 1. You can't raise any of your scores above 20.
Creature Type: For mechanical purposes, you are a humanoid.
Size: Frogs are usually about 3-5 inches long. You are Small.
Speed: Your walking speed is 25 feet. You also have a climbing speed of 20ft.
Extra Proficiency: You have proficiency in either Stealth or Survival.
Standing Leap: Your long jump is 25ft and your high jump is 15ft, with or without a running start. You may make a standing leap as a bonus action. If you do so, you may use your reaction to impose disadvantage on an enemy’s attack of opportunity. You may use this reaction twice per short rest.
Aquatic Nature: You have a swimming speed equal to your walking speed, and can hold your breath for up to 1 hour. You have advantage on Stealth checks to Hide in swampy terrain, or when submerged in a body of water.
'Don't Eat Me': Your skin secretes a poison that is harmful when ingested. You have advantage on Saving throws against being poisoned, and you have resistance to poison damage. In addition, when you are Swallowed by a creature, it must succeed on a Constitution saving throw at the start of its turn, the DC of which is equal to your 10 + your Constitution modifier + your proficiency bonus. On a failure, it takes 2d6 poison damage and must spit you out. On a success it takes half as much damage, and suffers no other effects.
Languages: Your character can speak, read, and write Common, Amphibian, and one other language that you and your DM agree is appropriate for the character. (See the list above for available languages).