Terrain Hazards: Warrens

Norway Rat Warren System.

The warren system is the home of burrowing animals. Lots of rodents and invertebrates, for example, have burrows. Obviously, these are normally too small for people, but in a fantasy setting, who cares. Giant rats, worms, ants, and killer rabbits don't need to be especially rare fauna, so tunnels that are yards wide don't have to be unusual. What are some interesting omni-present problems we can find in warrens? Let's find out.

Ick

This highly scientific category of substances is used to shore up tunnels.Sometimes it's dung, sometimes it is spit, it could be spider silk. All of these might trigger squeamishness or phobias in adventurers, but even more likely is a binding trap. The rules for Binding on p. 40 of Basic Set - Characters and p.42 of Powers have some good information on configuring a binding. If I were GMing it, I'd set the binding level of the trap depending on how hard it was blundered into. A light accidental probing might have a level of <50% of the character's ST or Escape skill. Blindly stumbling into it, might be on par with their best of the two; and somehow being forced into it by knockback or falling down might have a 20% or 30% superiority.

If you are a denizen of the burrow, you have probably some knowledge of how to traverse the substances somewhat safely. Someone with this advantage might be able to avoid the traps the same way someone might use acrobatics or perfect balance for pitfalls.

Swarms

This is probably weird to think of as a set-piece, but nonetheless, it is a rarely exercised mechanic that goes hand-in-hand with burrows. Rules for Swarms can be found in Basic Set - Campaigns on p.461. A swarm is an interesting challenge for an evasive or high damage character, but usually easily defeated by characters that use wide area attacks, like magic, bombs, or liquid projectiles.

For larger enemies, p.64 of Horror describes hordes of small animals, and p.91 describes hordes of large enemies. Hordes are an extension of a swarm, and have more to do with magnitude of numbers than anything else. Be familiar with the Rate of Fire rules if implementing hordes or swarms, these are slightly rare in low-tech or fantasy settings, but important to hordes.

If you are controlling a swarm or a horde, it's either trivially difficult or next to impossible to defeat the enemy depending on access to large area attacks. Animal instincts in a situation like this would probably lead to a dispersal if defeat is imminent, though some insects will fight to the last man. In the face of large area attacks, the best strategy is to thin out as much as possible and surround... unless the attack is an emanation.

Vertical Tunneling

Unlike man-made structures, animals are prone to using more vertical tunnel structures. This means fights can break out in very inconvenient situations like when climbing up or down ladders or ropes, while the denizens might walk on walls or ceilings like no one's business. If the denizens don't need ropes or ladders, they might see nothing bad about cutting a rope or knocking over a ladder.

I feel like I've seen rules for this somewhere but can't find it right now, so I'll make some stuff up. To maintain balance while striking and climbing, roll at -4 cumulative with other penalties to attempt to swing a weapon or what have you. Failure means you feel yourself slipping, and stop to catch yourself. Success means you can perform an action, possibly penalized for weird posture. Critical failure is falling.

If you think that you will be having people dangling over an abyss while fighting against giant ants and the like, it'd probably be a good idea to note ahead of time the appropriate fall damage for max, and maybe half distance to more easily extrapolate damage later. Some falling damage values can be found on p.19 of Dungeon Fantasy 2.

Other Thoughts and Conclusion

Walking into a giant animal's warren is nightmare fuel for me. A handful of heroes against hundreds? Thousands? of things that can each probably rip them limb from limb as a matter of instinct? No thanks, amigos.
A lot of the same things that apply to caverns, and mines apply here as well. Smart animals can reuse natural caves as part of their system, and well built burrows follow some of the same concepts of a man-made mine.

This is the end of the laser focused combat oriented set-piece view of each of these backdrops. I think I might come back and deal with more holistic details of each that seemed out of scope for this series, and add some interesting enemies that would feel appropriate for further evoking the feeling each should give.

This has probably been one of my fluffier and bigger stretches of a series. I feel most confident writing when I got mechanics and page numbers backing me up, but a lot of this has been conjecture and brainstorming, but I think working outside of comfort zones can be inspiring when you have a bit of a writing block. I feel less aimless now at least.