The tenth stage of the "Van Kanigem" tournament.

Regarding summoning the boat...
At first, I thought that the trick of summoning it was removed from the starting save to make the game more challenging, because it seems that "Summon Ship" is not initially available to any hero. However, if you reload the save and change the object generation, then this spell appears in the spellbook for new heroes in the tavern...
Now I'm wondering - where did the ship in the spellbook come from if everyone has the same save? :)

You could also read in the description that they have "cold immunity."
Do you have insider information?