If I'm interpreting his bio right, Raiden essentially IS electricity, in a concentrated form, with a consciousness, and a mortal body that acts as a vessel. When he released his "godlike essence," the electricity that comprised him dispersed in the blast, but afterwards it condensed again. I suppose he used the remains of his old mortal body, and pieced it back together. He probably healed the wounds where the parts were severed, but stayed charred as symbolism that he's now pissed.

^^^^^ coooooool, thanks

What if.....
In the fight with Shang Tsung and Quan Chi against Onaga, when Raiden unleashes his final blast, what if Shang Tsung's soul somehow entered Raiden in his weakened state? We know Tsung can absorb souls, why not expel them too?
I know it sucks but I was trying to think up of a way to bring Shang Tsung back and this was the most creative way (story-wise) that I could think of.

Remember, though, that's just my interpretation, not confirmed or anything. In his first-person bio he says his "enegies reformed in Earthrealm" after the blast, so what I said about him having a mortal body as a vessel is just speculation, because otherwise I don't know why he would reform charred, and with a tattered cape.

and he has red eyes.. because hes pissed at shinjinko... i will not give away his ending though..

i saw his ending also, but he always has his eyes red after the intro. and i still dont get it why he has that look.
and i know, XcarnageX, its just really cool the way you said it.

If you really want to know why he's charred it's hard to tell. Watch the beginning video and you will notice that even though Raiden unleashes the energy he isn't caught in the blast and neither is Quan Chi. Even if you have to squint, you will realize that they both teleport, leaving Shang Tsung to die. The charred body could just be an aftereffect of releasing so much energy from his body and the red eyes probably symbolize anger..i mean...who likes to have to waste all their energy on someone, find out it didnt work...and then realize that somebody you trusted released onaga.

There's someone in... I believe it's Outworld, who says that gods don't truly die; they simply reform after a short time. I believe what happened was that when Raiden reformed in Earthrealm, he simply reformed into a new aspect.
If anyone's familiar with the DC/Vertigo comic series Sandman, it's kind of like when Morpheus (aka, Dream of the Endless) died neared the end of the comic series, and a new Dream came into being.

EBLIS O'SHAUGHNESSY: Sir Librarian -- the young lord in white... who was he?
LUCIEN: He is Dream of the Endless.
EBLIS O'SHAUGHNESSY: He is...? But the wake. The ceremony. I was told that Dream of the Endless was no more.
LUCIEN: Yes.
EBLIS O'SHAUGHNESSY: So... who died?
LUCIEN: Nobody died. How can you kill an idea? How can you kill the personification of an action?
EBLIS O'SHAUGHNESSY: Then what died? Who are you mourning?
ABEL: A point of view.

Hope this helps...

Sort of like other people are saying, I consider Raiden's body to be a personification of what he really is. So when he unleashed the blast, I think that if it damaged him in any way, the damage would be reflected in his outward appearance. So if the blast weakened him, when he reformed, his new body would have reflected that damage. It also could have been that he was just pissed off, and wanted to show it as some people already have said. I suspect it’s a combination of the two.
I do disagree with the statement that it is a new “aspect” of him, because if he was ever badly hurt before this, in another MK, then you’d have a different god every time. I think his personality, whatever it is, has remained the same.

Darque Bishops right I also found in Konquest that this was the only way he could be reformed is in a dark form hence the name dark raiden that was mentioned when he wants to fight u in outworld in konquest!

I think it's the fact that it came down to Raiden having to take on the Deadly Alliance alone, after the mortals failed. When he returned, his new look was to basically show the mortals that he's not fucking around anymore.

I agree. I think Raiden is all evil-looking because after facing Onaga, his new attitude is that mortals are idiots and he must protect Earthrealm his own way.