My players have been slowly and steadily been chipping away at the forces of Ironslag, which is understandable because as written it is a GD fortress and it's denizens are militant by their very nature. The book has a pretty basic explanation of how the forge functions, but the way my players approached the situation made me take the reigns a bit more and try to assume the mentality of how a militant fire giant, hell bent on achieving his divine purpose, would react to small folk trying to take the lynch pin for his victory(My players are more personally invested in reclaiming Maegera than they are the conch, they actually already even have their level from acquiring the conch). In doing so, I fear I might be making things too difficult on the party.

The party started by killing the Yakfolk village and freeing all those slaves, a few close calls but nobody even downed; so far so good. Then they make their way down through the mines and take out the Salamanders and release a few more prisoners. It's at this time I decided that the Duke would have sent someone up the elevator to check on the Yakfolk, as anyone accessing the mines would need to go through them first. Between some slaves going missing in the mines and the visible destruction in the village above, Zalto decides to halt mining operations and shut down the elevator until the invaders have been dealt with to avoid losing any more assets.

After the party leads smaller raiding/scouting groups into ambushes in the mines, Zalto decides to abandon them altogether and post guards at the mine entrance and bottom of the elevator shaft. The party has a rogue/bard crime duo that have a broom of flying and can be invisible, so they continued probing into the forge, even managing to grab a substantial amount of loot and getting away in one piece. They get the conch and bust their way out, so I give them their level and they are even more bent on retrieving Maegera now.

For the first time since they arrived, the party knocked on the front door and tried talking to the giants, offering to trade the conch for Maegera. Zalto declines their offer, and informs the party he had slaves that were members of the same clan as the dwarf party members, and would not hesitate to kill them if the party continued to interfere. The rogue makes another invisible flight into the forge to recover the Iron Flask on Zalto, as they were able to determine that was the only way to transport the elemental. So now that the party actually has the means to take Maegra, I feel like the gloves are off and he is on full defense mode.

I had already made a makeshift barricade around the mine entrance from the shields of a FG dreadnaught the party had killed earlier, with a trap built in just for fun. The next thing Zalto did was put up a net of cables to seal the elevator shaft as best he could. I made it so the cable net just required an acrobatics to slip through but after the rogue was spotted trying to slip through again, they tightened the net further, increasing the DC. I'm not trying to make things impossibly difficult for the party but I can't help but think that Zalto would be trapping and sealing every entrance into the forge, putting all haste into finishing the Vonindod as quickly as possible while using small folk prisoners as hostages to buy him as much time as he can get.

TLDR: My players have been picking away at Ironslag for close to 2 months of game time for a secondary objective they decided is more important, and I'm not sure if I'm going too hard on them or setting appropriate consequences.