God and the Devil

If God exists as an all powerful being that is the source of creation, then how could the Devil possibly come into existence? 

Let's be logical, folks. If God didn't create the Devil, then "He" is not all powerful because a force exists outside of "Him" that works against "His" will.

If "He" is indeed the force supreme, then it is downright rude of "Him" to mold a larger-than-life evildoer that will "git us if we don't watch out," to echo a ditty of decades past.

It also seems impossible for any singular being - powerful prophet though he or she might be - to "die for our sins," although one could certainly be crucified by others because their sinful thoughts and deeds. As far as I know, people must pay for their own karma. In this day and age, if someone else is capable of taking on our karma and sinking their existence, that would be called co-dependence.

I will admit that reading the Bible has been a far too arduous experience to endure, even if Donald Trump claims it is akin to watching a great movie over and over again. However, if any Bible  devotees can offer a good answer to my logical questions, the floor is open.