Spike trap

For tips on how to use spike traps in general or in killboxes, see Defense structures#Spike traps and Defense structures#Entryways.

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 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

Spike traps are single use traps that may be triggered when a pawn of any kind walks over it. The base trigger chance is 100% for enemies, including animals affected by the manhunter mental state. Non-manhunting wild animals have a 25% chance to trigger the trap, and colonists and tame animals have 0.4% (one in 250) to trigger the trap. However, colonists and both wild and tame animals are aware of the location of traps, and will avoid pathing over them if reasonably possible. Friendly visitors will never trigger a trap. 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.

When triggered, the spike trap makes five attacks against the pawn that triggered it. Each attack does Stab damage. 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.

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

Analysis

A single trap can be fatal to humans or large animals if it is made of good materials. The base damage varies according to the material it was built from. The damage type is sharp melee, which strikes mainly on the head and torso and usually causes bleeding. Traps are very helpful when dealing with early/midgame raids, and almost essential in higher difficulties.

Wood traps can be quickly created and placed in large quantities. Although stone spike traps take large amounts of time to make, they can kill a raider in one trap. Building stone traps can be a good activity when one has the Work Frenzy Mental inspiration.

Stats table

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

Material	Total Damage	Attack Damage	Armor Penetration
Wooden Spike trap	40	8	12%
Granite Spike trap	65	13	19.5%
Limestone Spike trap	60	12	18%
Marble Spike trap	60	12	18%
Sandstone Spike trap	50	10	15%
Slate Spike trap	60	12	18%
Jade Spike trap	100	20	30%
Golden Spike trap	75	15	22.5%
Plasteel Spike trap	110	22	33%
Silver Spike trap	85	17	25.5%
Steel Spike trap	100	20	30%
Uranium Spike trap	110	22	33%

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. Now much more powerful with a 100% chance to spring on targets, and has armor penetration depending on what it’s made of but requires resources to replace.