Goro's dad is named Gorbak, and he was still alive during at least MK2 since he appeared in Tobias's comic, presumably he lived all the way to Armageddon as Goro was always "prince", and would've become king if his dad died.

Durac was his brother according to a cartoon by Threshold. He's never been mentioned in canon.

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The helmet being a Shokan's skull could make some sense, though, if you go by how it used to look in the old timeline. It used to have a row of little spikes on the top, and depending on what piece of art you saw, Sheeva didn't used to be the only Shokan with forehead spikes, Goro was sometimes drawn with them and presumably their whole breed were meant to have them.

I thought it was Onaga's head...now THAT would be one badass war trophy, even though he just poisoned the Dragon King.

...still, Onaga.

I'm pretty sure Onaga's head is the wrong shape to fit. For one thing, he's got giant curved horns.

Aren't his horns...part of his helmet??

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I'm honestly not sure how the fuck Onaga's helmet works, how much of it is detachable and how much of it is his own head. The horns were part of the helmet on the MKA konquest kollectible, but I don't consider that a trustworthy example, and he's not seen with the helmet off anywhere in the games. I don't think he'd look particularly dragon king-like if the horns came off with the helmet.
Oh also, I just thought of another reason the helmet can't be Onaga's head.
We've seen Onaga's original body in its coffin, in Sindel's MKD ending and in MKA he's inhabiting his original body instead of possessing Reptile. His corpse still has its head, so Kahn can't possibly be wearing it.

This is a very interesting topic that I'd never thought of before. Good show!

Indeed, Goro used to have the little head spurrs right in from of his ponytail in both the MK1 game image, the early toys and the Malibu comics. I remember distinctly wondering why Kintaro didn't have them, but Goro and eventually Sheeva did. Why they got rid of Goro's spikes, I don't know. Sheeva kept hers. I can only assume that they are perhaps a sign of Shokan elite and when Goro lost to Lui Kang, he might have had his stripped out of shame.

The design of Khan's helmet certainly could be a Shokan skull with some additions to make it more dramatic. (ie. the embellishment horns in the front) In fact, that forehead addition looks to have been faceted into the forehead of the skull rather than being a natural part of the skull itself.

The "horns" on the front of the skullmask are clearly a bladed metal crest bolted on there the way samurai have them on their helmets.
His Shaolin Monks render is the only time they've ever actually made it look like two bone horns sticking out, and that always irked me, because when the rest of the render looks like a perfect recreation of his MK2 appearance, that one difference seems more like a "mistake/inaccuracy" than an "artistic choice". (Actually now that I look at it again, his belt buckle is wrong too.) At least he looked right in-game... though it always bothers me when the renders don't look like the in-game models. Isn't the whole point of doing a render to publicize what the characters in the game look like?

I don't know if we really need an explanation for this. I always assumed that it was just a regular war helmet that Shao Khan wears because its intimidating. I don't think explaining where it came from would add too much to his story.

Well he never takes the damn thing off, even when he's just chillin' on the throne talking to his subjects and "daughters". Maybe there's a reason. 'Course, it's probably just the devs not having time to or interest in making a helmetless alt costume for him. Tobias and the Malibu artists drew him not wearing it all the time back in the 2D days, so at least the original version of Kahn had no problem showing his face in casual situations.

And then there's the fact that the reason Reiko wants to wear it is he considers it the crown of Outworld. It's not that he wants to run around in Kahn's clothes, it's that he wants to be king.

Or this too. Reiko also says after you complete his mission in MKD's Konquest


"One day, I WILL rule as Emperor of Outworld!"

Maybe he thinks that wearing Kahn's helmet will transform him into a warlord of unprecedented savagery...? Hmm...

That...seems terribly unlikely. Pretty sure he just wants to wear the symbol of the office.