Most of us use our eyes...
All kidding aside, the most common way to identify a Christian is their core belief in Christ as the Lord and Savior, coupled with and understanding of the Holy Trinity. (IOW, we do not become gods in our own right upon death)
Also, the Bible was Canonized with the understanding that it shall not be added to. Ever.
The Book of Mormon defies that edict.
When did this happen and by whom?
There is no edict that the Bible will not be added to forever. There is an edict that Revelations shall not be added to forever. Perhaps you are as mistaken about that as you are about the rest of the Church of Jesus Christ of Latter-Day Saints.
How? I'd like to see your answer.
Sounds like: "We don't want to hear any more from you!"
Not a bad idea of God's.
Also many scriptures about false prophets and the many that would come in His name.
Imagine without the admonition to not add to the Bible, it would be possible for LDS, Jehovah's Witnesses and Islam to be accepted as valid revelations from God.
I notice that all of the hard questions put to the apologists are not answered.
Just refuting of scriptural passages and references that deny the creations of more Abraham based religions.