I voted for King of Tyrus for three key reasons:
First, orange is one of the worst brigades/themes in T1 right now, which means that, although Wandering Spirit was one of the cornerstones of a demon defense, he's next to worthless when it comes to competing at top tables. King of Tyrus, functioning primarily as a standalone evil character, can really be splashed into almost everything. I think in T1, the point definitely goes to King of Tyrus.
Contrast that with T2, and really, I don't think the results are much better. Admittedly I don't play much T2, so I don't know what the meta looks like for sure, but the vibe I get is that orange really isn't that good in T2 right now. Wandering Spirit is amazing in T2, and again, is really the cornerstone of a solid demon defense, but if the brigade isn't that good, the evil character isn't either. King of Tyrus is not nearly as good in T2 as he is in T1, and honestly, the point probably goes to Wandering Spirit here, but it's much closer than in T1.
Ultimately, which evil character is likely to get the most blocks in a given game? The answer is KoT.
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