(MASSIVE SPOILERS!) I JUST REALIZED SOMETHING VERY IMPORTANT!

I don’t think he can regenerate from just the head. Like a salamander can grow a leg back but a whole salamander can’t grow from a leg. 

CAN'T WAIT TO READ THIS!!!!!! JUST HAVE TO KEEP MY EYES CLOSED!!!!!!!!!!!!!!!!!!

Nah - He's dead - I think (hope?) they are settign up Mecha King Ghidorah

 Yeah, I don't think the body can regenerate from the head. Only limbs and heads can regenerate from the body, as long as his vital organs remain intact. We see Godzilla step on Ghidorah, crushing his body with immense force.

However, we do see Ghidorah's head still roaring when Godzilla has it in his mouth before exploding it with his breath. But I suspect the animation of his head would have been short lived anyways.

Makes sense, but I stand by my theory that we haven't seen the last of Ghidorah

The head seemed pretty dead in the post credit scene.

Wait post credit scene?

There was a scene with it in the post credits. You had to stay to the very end though.

Yeah, I just saw it, the head was decaying, probably has something to do with the oxygen destroyer being used

'The body couldn't grow back from the head.' Not in the real world no, but heads don't grow back either. Tails, legs, sure but not heads. But anything's possible from this film

They do imply that the head will be used for something in the post credits scene. Perhaps man made monsters using DNA from the head? Remember, KG is an alien. We have no idea what it is truly capable of.

It is kaiju.

It is King Gidorah.

It is Monster Zero.

It is alien.

I think - yes.