Discussion about Necropolis heroes.

Markel has an amazing ability, I agree, but Zoltan has an even better one.

And how often do you play as Zoltan? Dude, he's great for the endgame, but mediocre for everything else. And he can't compare to Markel at all (except on maps where undead are a problem), which is why Markel is only in the campaign.
Personally, I like Deirdre (besides Zoltan), if you don't mind playing as undead.
Although Vlad was really strong before version 1.3, but he was nerfed a lot. Plus, everyone got Rise Dead.