The party spent many months together slaving away in the mining chambers. Each day they'd be tasked to mine out the pink crystals of the caves and deliver them to their druegar overseers. They were given gloves and warned never to touch the crystals unless they wanted their hands to melt off.
Earlier in the day their deep gnome companion overheard the druegar talking with a higher ranked taskmaster. "Why is this group still working?" she heard "They are too close to changing. They should have been gassed at least a week ago! Do it tonight or join them tomorrow."
Not knowing what this meant she passed the information onto her group. When they were alone in their cell the group desperately searched for a way to escape; when a greenish gas started to seep in through the vents. With a new sense of determination and a strength of blind panic they were able to rip off the door of the prison and escape.
In their escape they came across a small group of druegar. Dispatching them and stealing their pick axes, a large pink crystal, and keys that they use to remove the anti-magic shackles around their wrists. Weaving through the narrow tunnels of the Underdark they eventually fled into a small cave to catch their breath. But they held it once again as a druegar and his mind flayer lord passed by the cave mouth. They overheard bits of their 'conversation'. "No, they haven't changed yet", "Yes, we think it was contained to just that one cell", "No, we don't think Haven is involved".
Fleeing once again the group enters a tunnel that forks down two paths. Upon careful inspection the sharp rocks in one path are actually teeth! The group jumps down the other path after hearing two druegar entering the cave. Their loud noise wakes the Purple Wurm that was the other cave which chases after the druegar.
Further down their tunnel the group meets a small group of armed terrestrials, including a dwarf named Draggen. Draggen has the party touch the crystal which grants each of them a new special ability. He then offers to trade them their crystal for access into Haven and takes them there.