Your dexterity score increases by 2, your strength score decreases by 2, and one other ability score increases by 1.

Pseudodragons mature fairly rapidly, and reach adulthood around the age of 14. Most that make it to an old age can live to 120. There have been rare stories of those who have lived much longer around 200 years of age. 

Most pseudodragons are kindly, and tend toward the good alignments, but they are also quite capable of cruelty, greed, and spite. Many pseudodragons also feel the spark of wildness and independence common in dragons, and tend toward chaotic alignments. 

Pseudodragons are the size and weight of a large housecat, though with their tail, they are closer to 3 feet long, and possess a similar wingspan. Your size is tiny. 

Your base walking speed is 15ft

Accustomed to life underground, you have superior vision in dark and dim conditions. You can see in dim light within 60ft of you as if it were bright light, and in darkness as if it were dim light. You cant discern color in darkness, only shades of gray. 

You have a flying speed of 30ft. To use this speed, you cant be wearing medium or heavy armor, and you cannot hover.

You can speak common and draconic

As a tiny creature, you interact with the world differently than your larger peer. You have the following rules; You take up the space of 1' cube; you may move through the space of a size medium or larger creature, and vice versa, though his movement is still considered as difficult terrain. You have advantage on climbing checks, but disadvantage on all other strength checks. Finally, you cannot wield normal weapons. 

With your mottled scales and small size, you are naturally adept at sneaking as well as your keen eye for what is going on around you, you gain proficiency in both stealth and perception.  

You possess a vicious bite that you may use in combat. When using your bite, your unarmed strike deals 1d4 piercing damage. This weapon is considered a finesse weapon. 

You may make an attack with the venomous barb on your tail. On a hit, the target takes 2d8 poison damage and must make a constitution save (Save DC =8 + your constitution modifier + your proficiency bonus) or be poisoned until the end of your next turn. Once you have successfully used this ability, you may not use it again until you complete a long rest. 

Once per short rest, you may use your reaction to gain advantage on a save against a spell or magical ability.