It sparked quite a discussion about the Overlord. Yes, he is powerful and cunning, but not all of his plans go as intended. Although "Dark Messiah" (?Mod) has two endings, and one of them is a good one, it means that the Overlord was on the verge of failure with his plan, not anticipating everything. And with such capabilities, unique magic compared to other factions (no one else can manipulate their appearance and transmit their images over a distance), and the largest army in Ashan (as you yourselves said), he couldn't execute his plan properly... It seems a bit weak.
Apparently, the Overlord blindly believed Sar-Shazzar. It should have happened exactly that way, according to the prophecy. But it never happens that evil wins, so the developers of "Dark Messiah" "provided" a second option.
I voted for Tieru and still don't regret it: first of all, he is, after all, a Dragon Knight. Besides, he knew about the demons' conspiracy, healed Agrael, and gave him instructions (which later turned out to be the only correct ones). Even after death, like Qui-Gon or Obi-Wan from Star Wars, he managed to stay in Ashan of his own free will to "give" instructions to Findan, and of course, to Railag. He was also obviously a very powerful elemental mage (creating fog over the entire archipelago is no joke).
In general, theoretically, Sar-Elam should be the strongest, if we are talking about the Overlord. After all, he imprisoned the Overlord and all the other "nasty" creatures in a single spell.
