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Here's a cunning wizard, this Cyrus, lol.
New here? I'm Roha — want a quick tour?

Marckel's specialization only works on Necropolis undead creatures (and Death Knights are not creatures of that faction).
But I keep seeing posts everywhere that the Knights "join," maybe it depends on the game version or difficulty? I'm playing version 1.60.
One of the stacks joins you in the second mission (there are two of them).
They are also present in Heroes of Might and Magic III, somewhere on the islands, and I also had to defeat them.
Marchel's specialization only works on Necropolis undead creatures (and Death Knights are not creatures of that faction).
It's strange, though. After all, Death Knights are undead, and this is stated in their characteristics; if you click on a unit, you'll see it. And for Markel, the specialization is to recruit all neutral Necropolis undead units. So why did they decide to exclude Black Knights from Markel's recruitment?
Well, surprisingly, 8 players joined in mission 4. Yes, they are undead, but the description doesn't mention the castle they "belong" to, see:smile17: