So i am just about done with Blackwall Keep and I coul dfind no reason for the PCs to end up in the egg chamber. Here is how it went...
They took a bunch of right turns and ended up facing off with the king pretty quick... drinking grog on his throne. (it was late at night and I didn't want him to be sleeping like many of the soldiers were) The mage runs around the corner and throws in a fireball, which does pretty minimal damage... the King in turn slams the mage with a crit from the trident and takes the mage down. They start taking a bit more caution and eventually take the king down. The Shaman approaches from the the rear and brokers the deal of hostages in exchange for the PCs trying to secure peace with the Free City. All is agreed...
Now why in the hell would the shaman ask the PCs to go into the egg chamber? Maybe he doesn't trust the dragon... I thought about that, but would he trust soft-bellies in the egg chamber either? I am thinking about having it have turned into a nasty little hole filled with Kyuss spawn if and when they return with the peace deal...
How did others handle this situation. I just couldn't come up with a reasonable excuse to get the PCs into a situation where they would go in there. The module offers a huge bonus (3,500 XP each!!!) if they go in and kill the spawnlings without damaging the eggs... but the only way I see them coming to this room is if they just slayed the shaman and they are plowing through looking for loot.
~Jamey