The Omega (voiced by Zach LeBlanc) is the Oni leader and wields a Staff. He seeks to erase creation and cover the realms with darkness.
After the creation of the First Realm, Mr. Realms created Omega and Fristbourne. They eventually gave birth to The First Spinjitzu Master but after a war broke out the First Spinjitzu Master left the realm to create Ninjago. The Omega created the Oni and sent them after the First Spinjitzu Master but they were defeated and sent back to the First Realm except for Mystake. Then the Omega sent The Overlord to kill the First Spinjitzu Master, but he ended up being banished to the Dark Island. Then the Omega created four Oni Masks (From which one came to life) and hid them in Ninjago but made sure the First Spinjitzu Master will never find them.
The Lego Crossover
The Lego Crossover Videogame
Omega is an unlockable character in the Lego Crossover Videogame. He wields his staff as a weapon.
Darkness (Omega can summon dark tentacales, which turn enemies to stone)
Pole Vault (Omega can jump using his staff)
Drone (Omega can summon other Oni to defeat enemies)