Your Constitution score increases by 2, and your Wisdom or Strength score increases by 1.

Due to your scales and the shape of your body, you are ill-suited to wearing armor. Your armored body provides ample protection, however; it gives you a base AC of 17 (your Dexterity modifier doesn’t affect this number). You gain no benefit from wearing armor, but if you are using a shield, you can apply the shield’s bonus as normal.

Accustomed to life underground, 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

A creature with tremorsense can detect and pinpoint the origin of vibrations within a 30Ft radius, provided that monster and the source of the vibrations are in contact with the same ground or substance. Tremorsense can't be used to detect flying or incorporeal creatures.

Your claws are natural weapons, which you can use to make unarmed strikes. If you hit with them, you deal slashing damage equal to 1d4 + your Strength modifier, instead of the bludgeoning damage normal for an unarmed strike.

As an action you can dig through Loose soil with your claws as if you had a shovel; doing so you can tunnel at a speed of 30 feet. The tunnel collapses behind you as you go. You can use an action to attack a target from beneath with your claw attack; the targeted creature must make a DC 13 dexterity saving throw, on a fail you have advantage on your attack roll.

Your tongue is of the length 2/3 of you body length and  can be used as an extra hand. 

As a bonus action, you can use you tongue to manipulate an object, open or close a door or container, or pick up or set down a Tiny object. The tongue cant wield a weapon, but  can activate magic items, and lift up to 10 pounds.

Pangolin have semi-prehensile tails for climbing trees. Females use their tails to carry their young, too.

Your Tail can be used to grapple a Medium/Small Creature as a bonus action.

As an action you can curl up into a ball to increase your AC. You gain a +5 bonus to your AC and advantage on constitution and strength saving throws.  While curled up, you are prone, your speed is 0 and can’t increase*, you have disadvantage on Dexterity saving throws, you can’t take reactions, and you can't take actions other than a bonus action to "Rollout" or uncurl.

While you are in a Defense Curl you can use a bonus action to travel a full 30 feet trampling every creature you hit until the end of the action. Any creature in your path must make a Dexterity Saving Throw. The DC for this saving throw equals 8 + your Constitution modifier + your proficiency bonus. A creature takes 2d6 damage on a failed save, and half as much damage on a successful one. The damage increases to 3d6 at 6th level, 4d6 at 11th level, and 5d6 at 16th level. After using this action, Defense Curl ends and the next attack against you has advantage.

Due to your love and affinity for all things natural, you have gained an ally in a size small or tiny beast with an INT score of 3 or lower.  If your companion dies at your hand or due to your negligence, you will no longer attract animal companions in this manner.  Otherwise, you can find another beast that fits the criterion to become your new ally after 1d4+2 days.  You also have a knack for de-escalating situations involving hostile beasts, as you can cast Animal Friendship once per long rest