#4 Baron Corbin
Baron Corbin and Kurt Angle don't have the same history as with Brock Lesnar, but the two have a reason for a feud nonetheless. The 'Constable' has been nothing less than a thorn in the side of Angle over the past few weeks, often cancelling Angle's decisions, and using the power that Stephanie handed him to be a pain for Angle to deal with.
Not only did Angle have to deal with that, add that to the fact that Corbin has only looked out for himself, making decisions that would benefit him. He was also a huge part of the reason why Angle had to take the 'vacation' in the first place.
Given all of this, it would make sense for Kurt Angle to return and take on Acting Raw General Manager for a feud.
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