Marxists do not follow the Christian principle of absolute good or evil. I would say morality is a groundwork concept, thus illustrating a very important difference between Marxist and Creationist thinking.
If you put a sampling of all Christians sects into the mix, you will likely find quite divergent views of the "truth." A Catholic man can drink but have one wife. A traditional Mormon can have many wives but can't drink. Something here is not "Absolute." Now you might say Marxists are a murderous lot. They spent a lot of time killing their enemies. So did European Christians. The killing may be more to about keeping a despot in power rather than about ideology.