Kratos1

It's quite simple,but it took me a while to figure out.
Ok so first he's going to throw barrels of explosive stuff at you,and you have to shoot them before he throws them.Repeat this process.Soon he'll set on fire and come and chase you.Lure him to a group of barrels and he'll light one on fire.The hard part is keeping him there.When you do,it will blow up,taking a chunk of his health,and yours if you don't move.Repeat this as well.Soon the Russian will be Russian Bacon
Hope I Helped!