#3. He found a perfect schedule that suits his body

If you've noticed over the past couple of years, The Undertaker has slightly adjusted his schedule to fit in a few more dates. 2018 saw him become more active than ever during his part-time run as he competed at The Greatest Royal Rumble, Super ShowDown (in Australia) and Crown Jewel less than a month afterwards.
While The Undertaker did admit in an out-of-character interview that he wants to be more careful in selecting his dates, he seems to have found a good type of schedule that suits his body and more than likely suits him financially as well.
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The Undertaker is practically guaranteed to be at every Saudi Arabia show and we'll definitely be seeing him twice a year. However, he seems to be keen on quick returns as well, which probably means he found a good pattern to work.
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