The strongest castle in Heroes of Might and Magic IV.

GENIE!!! Although there are other worthy ones! And what magic do they have! And what titans!

You are right, GENIE!!!
I'm not saying that if there wasn't a genie, it would be the weakest castle! NO! But simply, if it weren't for him, it wouldn't reach the top and gain glory.
A castle can do without a Titan (in principle), for example, by building a constructor on an iron dragon. But without a genie, this castle won't get very far!!!