Questions. Need some help populating my dungeon

[graydoom]

1. The fanatics in my dungeon are actually going to be prepared to repel adventurers. At the front I plan on having them arrange one of those large siege type devices that when fired shoots 10 spears at the target. Are there any rules for this I can use?

You could just scale up the ballista rules on page 152 in the DMG. Each spear would get an unmodified attack roll (just a d20), each spear or bolt would do 3d6 damage on a hit, and it would take 1 person 3 full-round actions per spear or bolt to reload and them.

 

[Wicht]

I would just have the spear machine do multiple attacks and have each successive attack per round have a lower chance to hit due to the kick of firing. Of course spears that missed the one in front might still hit someone behind them.

 

[JacktheRabbit]

The idea is a weapon built around 10 tubes each holding a spear. A large bar that is held back is released and strikes the butts of all 10 spears throwing them all forward at the same time.

I would just have the spear machine do multiple attacks and have each successive attack per round have a lower chance to hit due to the kick of firing. Of course spears that missed the one in front might still hit someone behind them.

 

[Darkness]

I'd handle the spear machine similar to traps, but that's just me.