Queen – “The King’s Sunset” [Campaign 1, Mission 5]

Did you spend 2 months building up your army? There are only legions of demons in the garrison.

And what about the Berserker?

Agraal descends after Godric disappears from the map, then Nikolai arrives and confronts Agraal head-on, and that's it. Mission over.

Exactly, he descends. But he will only kill Nikolaus after the tournament, and therefore he can be intercepted.
Personally, I was just interested in how correctly the scripts are written, or whether the developers relied on the fact that no one would kill Agraal. The campaign itself is very easy, so I wanted to experiment.