Editing Building destroyer

{{Quality|Exceptional|09:27, 18 May 2015 (UTC)}}

'''Building destroyers''' are creatures with the {{token|BUILDINGDESTROYER|c}} token and will actively seek out various [[furniture|furnishings]], [[workshop]]s and other [[building]]s and topple or destroy them. They come in two varieties, the first being annoying, and the second dangerous.  Most buildings will be "toppled" (deconstructed), leaving the building material or furniture unbuilt but otherwise unharmed, however [[door]]s, [[hatch cover]]s, and [[floodgate]]s will be damaged until destroyed, not deconstructed.

Building destroyers will destroy nearly '''all''' types of buildings they can reach, whether or not they block their path - [[door]]s, [[floodgate]]s, [[hatch]] covers, vertical/horizontal [[bars]], floor/wall [[grate]]s, [[statue]]s, [[workshop]]s, and even furniture are vulnerable. The only buildings that will be spared by a building destroyer are [[well]]s, [[bridge]]s, [[road]]s, [[trap]]s (including [[lever]]s and track stops), [[animal trap]]s, [[chain]]s, [[cage]]s, [[stockpile]]s, and [[Trap#Upright Spear/Spike|upright weapon]]s. They can destroy most furniture and buildings from a lower [[z-level]] when a valid path exists to that furniture, though locked hatches and closed grates are safe as long as no alternative paths exist. Building destroyers will path to and destroy even opened (or stuck open) doors, hatches, floodgates, or vertical bars. They will cause damage to any attached mechanisms during building destruction, sometimes leading to the unlinking of furniture to a lever before the furniture in question is fully destroyed.

Building destroyers cannot destroy buildings unless they can path to the building on the building's z-level. This means that building destroyers cannot destroy, for instance, a forbidden hatch above them (note that non-forbidden, i.e. passable, hatches are vulnerable!), or a magma forge from the magma underneath it '''unless''' a clear alternate path to the building exists.  

 

Building destroyers can destroy buildings from the z-level below while standing on a ramp or stairs that leads up to the building's z-level.

 

Building destroyers cannot destroy closed floodgates or locked doors from a ramp leading up to the level of those buildings unless there is an open path to the same level.  This was tested with trolls, in an entrance-way accessed by both lever-controlled floodgates and a manually locked door.  Ramps led up to the floodgates and the door.  When both were closed, the trolls showed no interest.  When the door was unlocked, a troll began to destroy it.  When the door was locked again, the troll went away.  When the floodgates were opened, a troll returned and destroyed the locked door from the ramp outside, while the open floodgates were also apparently being destroyed from the ramps by other trolls.  This may be related to the bug where Dwarves appear to be building diagonally as long as they can access the spot orthogonally.  It is unknown whether this applies to an open path extending through the full length of a fortress, rather than just a few steps away through open floodgates.

 

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Here, the {{Raw Tile|B|#F00|#000}}uilding destroyer cannot pass through the cyan door while it is forbidden, but the instant the door becomes unforbidden, the building destroyer will destroy the door-- from the tile on which it stands.

 

 

 

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Here, the cyan hatch cannot be destroyed while it is forbidden, but when it is unforbidden, the {{Raw Tile|B|#F00|#000}}uilding destroyer will destroy it.

 

 

 

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Here, the {{Raw Tile|B|#F00|#000}}uilding destroyer will stand on the ramp and destroy the door (or any other furniture), regardless of whether the door is forbidden.

 

 

 

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Here, the {{Raw Tile|B|#F00|#000}}uilding destroyer will be unable to pass the door if it's forbidden; should it become unforbidden, the building destroyer will ignore the door (probably passing through in order to target a different piece of furniture).

 

 

 

 

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Here, the {{Raw Tile|B|#F00|#000}}uilding destroyer has path to a square from which it can destroy the cyan door-- thus, '''it can destroy the door, even if forbidden, from the tile directly in front of it.'''

The simplest way to keep destroyer L2's from targets is with walls or channels.  A [[bridge|drawbridge]] will act like a constructed wall ''(if up)'' or floor ''(if down)'', blocking building destroyer 2's without that danger of being destroyed.