1. He can die. It's part of his species natural habits to avoid that by regenerating the damaged with a shizload of energy. Shoot him while doing so,he's dead. Kill him before he regenerates,he's dead. Block the regeneration,he'll die just like normal humans.
2. This "magic wand" is actually a multifuntional computer like device which is used for opening/closing doors, hacking technic and similar. Doesn't work on earth,stone and wood and such. Can be blocked, hacked, controlled and evrything else of this kind like every other normal computer.
3.He has limits,his lies in his long-term lifespan and with that in his emotional psychology. His biggest strength is also his greatest weakness.
4. I think it's sad how a fan of a show which teaches to love and tolerate others even while being hated itself is now doing the same on another fandom. And i used to be pegasister myself, i know what i am talking about.
And even beside that, it's in general not really polite to say mean things to other people on the internet. You can have your opinion, you can talk about that with people you, but please restrain from throwing it on other peoples head.
Also, if you don't like it, why did you click this picture?