White Oni, Steel Skin- As a White Oni, your skin is naturally more powerful and enduring than other races and can even harden at will. Due to this ability, you gain an unarmoured AC equal to 10+Strength Modifier+Cont Modifier. Additionally you can use your reaction to add 5 to your AC when you are attacked and can do this a number of times equal to your level, these uses refresh on a long rest. You gain +1 Strength as an Ability Score Increase.

Darkvision- You have 60ft darkvision meaning that in darkness or dim light you can see as if it were perfectly bright, but you can only see shades of gray rather than colors.

Magical Lifeline- When you are downed by a spell, magical weapon, or other such magical effect, you can add your constitution modifier to your death saving throw. Should your roll reach a 20 or higher, you can instantly get back up at 1HP and if you rolled over 20 add that number to your regained health (So if you roll a 25, you will rise with 6HP).

https://www.dndbeyond.com/classes/barbarian

Grappler - https://5e.tools/feats.html#grappler_phb

Great Weapon Mastery - https://5e.tools/feats.html#great%20weapon%20master_phb

http://dnd5e.wikidot.com/barbarian:giant lul

Oni Warclub - 1d12+1 bludgeoning damage

Onis Fists- 1d6 + 1 bludgeoning damage