Why might the Duergar invade a Deep gnome settlement?

[Jellyburd]

I'm not too familiar with the lore of deep gnomes or duergar, but my PCs found themselves in the (upper) underdark.
I want them to come across a gnomish settlement under seige or preparing for battle with the duergar.
My question is, as the title states, why might the duergar want to attack a gnomish settlement? I'm sure my PCs will ask.

[Spiderguy24]

I'm not too familiar with the lore between the two races myself, but here are a couple of suggestions.

1) The Duergar are being controlled by a Mindflayer colony that wants the Deep Gnomes irradicated or captured for their twisted experiments.

2) The Duergar are working with the Drow to claim the city and obtain a powerful relic the Gnomes have been holding.

3) The Duergar aren't Duergar at all, and it's really an army of demons under a powerful illusion spell to make them look like Duergar, possibly to make the Deep Gnomes declare war on their neighbors and weaken both sides to make it easier for the demons to finish the job.

[Daphne]

why might the duergar want to attack a gnomish settlement? I'm sure my PCs will ask.

They might want to take the Gnomes as slaves or want their territory because it's full of rich mines of valuable ores.

[Wilb]

"They live close, are small and squishy and can actually be forced into crafting stuff that is passable." - Duergar slavemaster.

They are kinda weak denizens of the Underdark, making them easy targets not only for Duergar, but for any group that finds them.

[Unoriginal]

I'm not too familiar with the lore of deep gnomes or duergar, but my PCs found themselves in the (upper) underdark.
I want them to come across a gnomish settlement under seige or preparing for battle with the duergar.
My question is, as the title states, why might the duergar want to attack a gnomish settlement? I'm sure my PCs will ask.

Duergars wants to have more slaves and ressources, so raiding a settlement might a way to get food, slaves, or ores and other useful things.

The Duergars also want mechanisms and industrialization to diminish how much work they have to do. If the gnomes have created an engine or another kind of useful crafting method, then the Duergars could want to grab it or their inventors.

OR: if the Duergars are invading rather than just raiding, it might simply be that the Gnomes's stettlement has a strategically important position or a source of something valuable nearby (like mines) and the Duergars want it.

[ImproperJustice]

The Duregar have an ancient and legally rightful claim to the area, but it had been abandoned for some time?

The Duregar themselves have been displaced and need a place to live.

There is a vital resource or it is the most defensible area and a greater threat is looming nearby.

A greater threat is coming, and the Duregar know the only way to defeat that threat is to deny it food, as the Duregar plan to retreat to an ancie next underground fortress and wait out the enemy.
However, the Deep Gnomes have had ben fruitful and cultivated massive storehouses of food, which the enemy will likely capture and use to sustain a longer campaign.
The Duregar, knowing the Gnomes will not trust them, must burn these storehouses to the ground in the hopes of preventing the greater enemy from surging onto the surface (idea stolen from the Fires of Ascalon- Savage Worlds).

The Deep Gnomes and their gadgets make an insufferable racket amplified by the cavern walls.

[Jellyburd]

The Duergar have an ancient and legally rightful claim to the area, but it had been abandoned for some time?
THIS!
That sounds like fun. See if they can resolve it politically rather than murder hobo style. I like it!
The duergar are definitely going to start as villains, (they witness them slaughter myconids) but if they did it as part of a desperate plan to take back essentially a holy site that is rightfully theirs my PCs might side with them over the gnomes...brilliant!

[ImproperJustice]

THIS!
That sounds like fun. See if they can resolve it politically rather than murder hobo style. I like it!
The duergar are definitely going to start as villains, (they witness them slaughter myconids) but if they did it as part of a desperate plan to take back essentially a holy site that is rightfully theirs my PCs might side with them over the gnomes...brilliant!

I would suggest having interested parties on both sides that would benefit from a peaceful solution and those that would prefer bloody, open war.

Have them try to influence the PCs with varying offers, and use escelating tensions as a “clock” to help the PCs make good use of their time.

Glad you liked the idea :)

[hicegetraenk]

THIS!
That sounds like fun. See if they can resolve it politically rather than murder hobo style. I like it!
The duergar are definitely going to start as villains, (they witness them slaughter myconids) but if they did it as part of a desperate plan to take back essentially a holy site that is rightfully theirs my PCs might side with them over the gnomes...brilliant!

Remember though that duergar are an evil branch of dwarves. The fluff says they are tainted by demonic blood, so a "holy site" to an evil race that lives in the underdark might very well be (should be) something very unholy and a good reason NOT to side with them. Depending on your party's personal goals and alignments ofc.

[GlenSmash!]

Most invaders want resources. Slaves for Labor, Land for farming or mining, settling a growing population.

[Jellyburd]

Remember though that duergar are an evil branch of dwarves.

But my PCs don't know that ;)

[RevelationMD]

Does this even need answering? They are gnomes - the dwarves are just doing your campaign world a favour :)

Seriously though - and I love the politics idea above - what about a forbidden love interest between one of the dwarves and one of the gnomes. Think ''short-side story''.