The following question contains major spoilers for the Storm King's Thunder campaign.
I'm currently running Storm King's Thunder for my party. This is for a home game (not Adventurers League). I just read up on chapter 10 of the book where the party visits Maelstrom. In this chapter, the party is supposed to have an audience with the Storm King's daughter, Serissa.
According to the book, the characters can approach this meeting in many different ways; they can take Serissa's quest for the coin, or convince Serissa that Iymrith isn't who she says she is. While I feel these are the most common approaches to this part, the book also talks about a scenario where the players take an aggressive approach and capture or slay one of Serissa's sisters before the meeting ("Dealing with the Giant Lords", p. 208):
"If the characters slay one or both of her sisters, Serissa is convinced that they are assassins who have been sent to finish off the royal family. She commands Maelstrom's defenses to destroy the adventurers. Serissa also reaizes that her faith in the small folk has been misplased. In effect, the killing of Miran or Nym gives Iymrith a major victory, so far as the act drives a wedge between giants and the small folk."
The book continues saying that the party can attempt to convince Serissa that her sisters are evil with a Persuasion check... But what if that fails - or my party does not pick up on this and just tries to fight their way out, either through the exit or by having to make new characters? By doing this, they could miss out on the alliance with the storm giants and they won't force Iymrith to her lair, both of which are needed to progress the campaign.
Did I miss something in the book which covers for some unexpected aggression from my party during this chapter? Or is there a way I could approach this so that it won't derail the campaign as much?