So Bored here a few links to prove things said in favor of religion commonly leading to mass loss of human life for no reason except the thinking "they are Pagans/heretics".
A few Wikipedia articles lol. 
[url=http://en.wikipedia.org/wiki/Religious_war]
[url=http://en.wikipedia.org/wiki/Religious_persecution]
A article from "The Guardian"
[url=http://www.theguardian.com/commentisfree/2013/jul/02/religion-wars-conflict]
Ask.com's answer to how much people are believed to have died due to religion
[url=http://www.ask.com/question/how-many-people-have-died-in-religious-conflicts]

If you also search Wikipedia you can easily find that the highest & lowest estimate for both all the mass murders done by "Communist" leaders and a single religious conflict the previously mentioned Taiping Rebellion are roughly the same with 100 million deaths as high estimate and 20 million deaths as low estimate, but the Taiping Rebellion is a single religious conflict which killed, arguably the same number as all "Communist" leaders in almost a whole century and in a period of time when this amounted to a percentage of the world's population that is larger than the percentage of world population which was killed in the Second World War.