I don't think Nomura has said anything about the Mysteriour Knight yet. So, what we know about the Mysterious Knight is that presumably he's Master Eraqus. I mean he has Master Eraqus's keyblade armor and related attacks. I mean the Enigmatic Soldier was Terra's Lingering Spirit right. So shouldn't the Mysterious Knight is Eraqus's Lingering Spirit? And if this is true, could that mean Master Eraqus will come back in KH3 or 3D?

maybe...i mean look at sezter

thats a thoery wise version of Terra-Eraqus. So he can return in KH3 or 3D

You mean the Armor of the Master? He is not canon. Just data of Eraqus, able to fight in the Mirage Arena.

 

/thread + and this V

The battle with the Armor of the Master happens in Mirage Arena which is pretty much a non-canon world, also making the boss battle non-canon as well.

So there isn't really much too it other than getting to see and fight Eraqus Armor. There's no big secret plot behind it like it was with the Lingering Sentiment and/or the Unknown from KH1FM.

The boss battle against Eraqus armor is simply just a fun extra battle

Thats true I forgot all about that.

Im sorry to say that fight never actually happened, it was... a mirage

Niether was Unknown as far as I know.

No no no nada zilch because when i first played bbs i almost went crazy trying to kill him and if i go through that again........ try not to think about that.

lf you level up to level 6O and up the Unknown is pretty easy.

Niether was Unknown as far as I know.

 

Well that fight was with a time traveller so its all relative if that fight actually happened

That hasn't been confirmed yet.

Niether was Unknown as far as I know.

 

MF himself is canon, but appearing in the past? No.

He was not canon to BBS.