Spike trap

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Spike trap

Spike trap

Five spikes under tension, connected to a touch-activated trigger. When the victim disturbs the trigger, the spikes spring forth and strike the victim. Since it is hidden in the surrounding terrain, it cannot be placed adjacent to other traps. Animals can sense these when calm.

Base Stats

Type
BuildingSecurity
Mass
2.5 kg
Beauty
-18
HP
40
Flammability
100%

Building

Size
1 × 1
Minifiable
True
Placeable
True
Terrain Affordance
Light
Cleanliness
-5

Creation

Skill Required
Construction 3
Work To Make
3,200 ticks (53.33 secs)
Stuff Tags
Metallic, Woody, Stony
Resources to make
Stuff 45
Deconstruct yield
Stuff 22 - 23
Destroy yield
Stuff 11 - 12
Technical
thingCategories
BuildingsSecurity


A spike trap is a single-use trap that deals heavy, but material dependent damage to the pawn that triggered it.

Acquisition

Spike traps require Stuff 45 Stuff (Metallic/Woody/Stony, 450 for SMVs), 3,200 ticks (53.33 secs) of work, and a Construction skill of 3. Spike traps cannot be placed or constructed directly next to each other nor next to any other kind of trap.

Summary

Traps are single use security buildings that may be triggered when a pawn of any kind walks over it.

  • The base trigger chance is 100% for enemies, including mechanoids and animals affected by the manhunter mental state. Note that despite the name, animals currently hunting a human pawn for food are not "manhunters" and are not considered enemies.
  • Non-manhunting wild animals have a 25% chance to trigger the trap.
  • Colonists and tame animals have 0.4% (one in 250) chance to trigger the trap.[Friendly Mechanoids?]
  • Friendly visitors and their animals, as well as revenantsContent added by the Anomaly DLC and sightstealersContent added by the Anomaly DLC will never trigger a trap.

However, colonists and non-manhunting animals are aware of the location of traps, and will avoid pathing over them if reasonably practical.[Path Cost?] One notable exception is roped animals being dragged by a handler - the rope limits their movement, overriding their usual behavior.

Prisoners are considered to be their original faction for the purposes of traps. Enemy who you have taken prisoner will retain their 100% trap trigger rate and will ignore traps when pathfinding. Colonists that you have taken prisoner retain their 0.4% trap trigger rate, even during a prison break, and will avoid traps whenever possible.

In all instances, the nimble trait multiplies the trigger chance for that pawn by 10%, that is, a 10% chance for enemies and 0.04% chance for friendly pawns.

Once a spike trap is triggered, it is destroyed. The "auto rearm" option, enabled by default, produces a blueprint to replace the trap.

Each spike trap is considered dirty with a Cleanliness of −5. This reduces the average cleanliness of the room it occupies.

Damage

When triggered, the spike trap makes five attacks against the pawn that triggered it. Each attack does Stab damage. This strikes mainly on the head and torso and usually causes bleeding. The amount of damage dealt by each attack is determined by the following equation:

Damage Per Attack = Trap Melee Damage * Material Sharp Damage Multiplier * rand(0.8, 1.2)/5

Where:

  • Damage per Attack is the damage each attack does to the target. A spike trap performs 5 of these attacks when triggered.
  • Trap Melee Damage is 100 for spike traps
  • Material Sharp Damage Multiplier is a material dependent factor.
  • rand(0.8,1.2) is a random factor between 0.8 and 1.2. This random factor is rolled once only and then applied to all attacks, it is not rolled for each attack.

The armor penetration of the attack is determined by the following equation:

AP = Damage Per Attack * 0.015
  • AP is the armor penetration of each attack.

Note that both the damage and AP of the attack in the info screen are misleading. The damage listed is the average sum of the damage inflicted, the AP is incorrectly calculated as if this damage is all dealt at once.

Analysis

Spike traps are invaluable in the earlygame, as one of the few defense strutures available. A hallway of spike traps can virtually end any frontal raid, short of tough or nimble pawns, without your colonists ever seeing combat. A single trap can be fatal to humans or large animals. Multiple traps can fall most creatures, short of thrumbos and heavy mechanoids. But as raids get bigger, it starts to get impractical to replace the traps.

Place traps where you expect raiders to go. Raiders will take the shortest, unobstructed route to a target. Unless they are sappers or breachers, raiders will try and break walls last. Common locations are in the corners of your base, where enemies will likely make turns, as well as narrow areas that receive frequent traffic. If it doesn't seem obvious to you at first, one way to find out is by studying raids that do come.

Material choice

Wood spike traps can be quickly created and placed in large quantities. Stone spike traps are cheap to make, and can kill a humanoid raider in one trap. But given the significantly increased crafting time of both the traps themselves and the stone blocks required to build them, it is often more efficient to simply make several wooden traps. Stone traps are helpful if you're limited by space or type of resource available, and can be a good activity when one has the Work Frenzy Mental inspiration. Metal traps are even stronger and don't take as much time to make, but are expensive in terms of resources.

Example of a trap tunnel. Raiders will fall into the traps. Colonists can open doors, and prefer to be slowed by the fences rather than walk through traps. If this is the only open entrance to a base, raiders will be lured here.

Stats table

  • Spike trap Spike trap Beauty Work to Build HP Flamma­bility Total
    Damage
    Attack
    Damage
    Armor
    Penetration
    Market
    Value
    Material
    Bioferrite Bioferrite Content added by the Anomaly DLC -18 008,000 ticks (2.22 mins) 80 75% 130 26 39% 63 Silver
    Gold Gold 2 002,880 ticks (48 secs) 24 40% 75 15 22.5% 4,510 Silver
    Granite blocks Granite blocks -18 019,340 ticks (5.37 mins) 68 0% 65 13 19.5% 110 Silver
    Limestone blocks Limestone blocks -18 019,340 ticks (5.37 mins) 62 0% 60 12 18% 110 Silver
    Marble blocks Marble blocks -17 017,740 ticks (4.93 mins) 48 0% 60 12 18% 104 Silver
    Plasteel Plasteel -18 007,040 ticks (1.96 mins) 112 0% 110 22 33% 430 Silver
    Sandstone blocks Sandstone blocks -18 016,140 ticks (4.48 mins) 56 0% 50 10 15% 99 Silver
    Silver Silver -12 003,200 ticks (53.33 secs) 28 40% 85 17 25.5% 460 Silver
    Slate blocks Slate blocks -18 019,340 ticks (5.37 mins) 52 0% 60 12 18% 110 Silver
    Steel Steel -18 003,200 ticks (53.33 secs) 40 40% 100 20 30% 97 Silver
    Jade Jade -8 016,000 ticks (4.44 mins) 20 0% 100 20 30% 285 Silver
    Uranium Uranium -18 006,080 ticks (1.69 mins) 100 0% 110 22 33% 290 Silver
    Wood Wood -18 002,240 ticks (37.33 secs) 26 100% 40 8 12% 62 Silver
  • Version history

    • 0.11.877 - Added as Deadfall Trap.
    • 0.12.910 - Rebalanced, cannot be rearmed.
    • 0.19.2009 - Renamed from Deadfall trap to Spike trap. Damage is increased, material cost and time to build are reduced, and it now has armor penetration (depending on what it’s made of) and a 100% chance to spring on targets and but now require rebuilding each time, rather than being re-armed at no material cost.

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