I don't think the Iranians will get involved. They talk a big game but everything about them is defensive in nature. They don't have much support at home as their currency is useless, water issues from mismanagement, their leaders are constantly caught breaking their own rules and life is getting harder and harder while many of their neighboring countries are filthy rich from the same products that are littered all over Iran (oil and natural gas).

China is a paper dragon. Has too many issues of it's own to try and get touch on in war.

Russia and Israel I can see.

The R family being wiped off the face of the earth would be nice.