So, raiga's story is this

[LUMOS ULTIMATUM]

He was the wielder of the lightning blade. After some time, he gave it to ameyuri ringo or she took it from him. Raiga didn't die whereas rumours and people think he died. Years later, Ameyuri ringo dies and was the one known as its last wielder but raiga stole it secretly. Later, raiga dies and leave the sword behind.

The reason kabuto revived ringo but not him can be :

1- Ringo was more versatile with the sword and the one who deserves to be reincarnated

2- Raiga's body was not found

3- His dna became unusable because he was electrocuted.

 

[Rohan]

Sounds Plausible but there is not enough content for him in the manga plotwise nor do I think there ever would be.

 

[reizon]

I don't watch fillers so I don't know anything people are talking about.!!

 

[Conspirator.]

Maybe this is true.

 

[LUMOS ULTIMATUM]

Sounds Plausible but there is not enough content for him in the manga plotwise nor do I think there ever would be.

I don't watch fillers so I don't know anything people are talking about.!!

Maybe this is true.

His story needs to be expanded.
To Reizon: He was in the manga of today.

 

[-Spoiler-]

I don't watch fillers so I don't know anything people are talking about.!!

He's canon now

 

[UltraPain]

Sounds good