I seem to have created something called MORT.

I made a plutonium nuke in "Destroyable Valley City" (my plutonium nuke is a large amount of plutonium surrounded by nitro all cased in metal and battery) and some weird element called MORT came up and I can't find it in the list. It burns a long time, which is an effect I really like.

I don't know how I made it, but what I really want is for it to be a main element. But for real, what is it? O_o

I kinda figured it was a secret element, but how do I actually make it in the game?

What I meant was by combining elements. Which was probably happening during that explosion I made.