Regarding the question of whether Saudi troops to enter Syrian territory from Turkey, Turkey's foreign Minister said that "it is only a desire"
http://tass.ru/mezhdunarodnaya-panorama/2665183
I do not believe this would be a WW3. As long as Russian ICBMs can reach USA mainland´s evil HQ. Probable scenario is some conflict between Russia and Turkey/Saudis which lets Us blame Russia and set new sanctions to kill economy. Ukrop hot Crimea/Donbass also possible. Regardless on facts all to be blamed on Putin/Stalin/Russia.
Interesting would look when Iran delivers not only weapons like AGTMs and Iglas to Kurds...not to mention own resources.
I mentioned it before - the goal of sauds/turks is a mini Syria govt by bandits to breed terrorism and instability with US/NATO blessing