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

You are an undead being created from unstable magic, who knows how long you'll live.  You might be biologically immortality or unexpectedly sputter out and die, you are the only one of your kind "alive".  Regardless, you no longer experience the effects of traditional aging.

Tieflings are about the same size and build as humans. Your size is Medium.

Your base walking speed is 30 feet.

Thanks to your infernal heritage, 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.

• You have advantage on saving throws against disease and being poisoned, and you have resistance to poison damage.
• You have advantage on death saving throws.
• You don't need to eat, drink, or breathe.
• You don't need to sleep, and magic can't put you to sleep. You can finish a long rest in 4 hours if you spend those hours in an inactive, motionless state, during which you retain consciousness.

You know the vicious mockery cantrip. Charisma is your spellcasting ability for these spells.

You can speak, read, and write Common and Druidic and Elven.