#1 The Undertaker
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Often called ‘the conscience of WWE’ (and for good reason), the Undertaker is revered for his dedication to WWE and his unyielding loyalty. He has been employed by WWE for almost 28 years, and in that time there has never been any backstage heat towards him in a major way.
The closest he has ever come to being punished for any wrongdoing was for agreeing to take a chair shot to the head from Triple H at WrestleMania XXVII. For that, he was fined, and he paid the fine without any issues.
The Undertaker has never gotten in trouble with WWE’s office and never has there been former backstage official in WWE ever spoken badly of him.
For further proof, just watch any video about Undertaker’s current and former peers. None of them ever say anything bad about him, whether they were wrestlers or backstage officials.
The Undertaker is, ironically, an angel in WWE, having never angered anyone backstage enough to warrant any ‘heat’.