I have a Mormon neighbor who did his missionary work in Thailand. My wife is Thai, so he came by to chat with us once with some missionaries who had visited us. I spoke to him for a while about his experience in trying to evangelize to a country that is 90+% Buddhist, and in which Buddhism plays a huge role in Thai culture. What I found fascinating is that in Thailand, a Mormon missionary was pretty much on a level playing field with any other Christian missionary. If a Thai person was considering a flavor of Christianity, the Mormon church isn't particularly "fringe" in the way it might be perceived by a Christian who is listening to a Mormon missionary in the US.

> Sounds like Mormons are only going after believers of Christ.

I can see why one may think this to be the case, because it invites you to pray in the name of Christ. In order to accept the invitation you need to be willing to offer that prayer. But the invitation starts with "We invite all men everywhere". It's not intended to exclude anyone.