What is the mechanism of Russians killed 13k Ukrainians in your opinion? Most of the fatalities are in the city of Donetsk and the surrounding towns. Even if the Russians were there as you state they were on the defence and the Ukrainian military was attacking it.
Who killed the civilians in this case? The simple logic says it was the Ukrainians military using artillery and air forces. Do you suggests the Russians bombed and shelled themselves in the city?
Well I guess that a win to even have you admit Russian military was in Donbass. Post 43 above shows Russian artillery, in Russia, firing across the border at Ukrainian forces. I'm sure those barrages didn't kill any civilians. You're like the crazy attorney that defends the wife batterer and blames the wife for defending herself.
“What is the mechanism of Russians killed 13k Ukrainians in your opinion?”
Christ Ivan, learn better English, or go back to Novorsibirsk.