"Brother Letter" is a short adventure set after the party obtained the Gem of Evocation in the ruthless entrails of the Cradle of Fire. Having survived the poisonous fangs of the Old Queen and the scorching spells of Arok, the heroes forgot about the curses in one strange old scroll. What will be the price of their carelessness?
Since this quest is not integrated into the main campaign and rather operates as a stand-alone adventure\map you'll need to make a few things. Imagine it's some kind of flashback or "what if?." Level up your characters!