If you mean keyblade as in Kingdom Hearts than I assure you that it is a mod that is installed from the internet.
The Oblivion Keyblade is the strongest Keyblade Sora can wield except for the Ultima Weapon, which is made through synthesis. The Oblivion is mostly black and purple with a cool design. The Oblivion is also known as the Dark Blade, which is opposed to the Light blade called the Oathkeeper, the blade given by Kairi.
The Oblivion Keyblade is given to you right before entering the castle at The World That Never Was, towards the end of the game. Riku gives the Oblivion to Sora.
Oath keeper is a key blade from Kingdom Hearts. it is the only keyblade to be fused with the keyblade oblivion
In kingdom Hearts 1, the best Keyblade is Oblivion, obtained in Hollow Bastion. In KH2, you have to synthesize it.
The Oblivion keyblade can be found in a treasure chest at hollow bastion after defeating Ansem for the first time.
After Roxas beat her, he absorbed her into himself, obtaining, Oathkeeper and Oblivion.
The Best Kingdom Hearts 3 Keyblade - Ultima Keyblade It has 13 Strength and 13 Magic, making it the best keyblade for both stats. It also formchanges into the Ultimate Form which is seriously cool. but i like this BEST Keyblade
After you defeat the Replica Riku, somewhere in that room is a Treasure Chest, and you'll get the Oblivion.
In The World That Never Was, after you defeat Xigbar and meet up with Riku
3 abillatie gears for obliven keyblade you don't know that?
In KH1, Sora gets Oblivion after beating Riku in Hollow Bastion the second time in a chest around the area that Sora fought him.
You're most likely referring to the Oblivion Keyblade, which is given to you by Riku (shortly before entering the castle at The World That Never Was).