In the rule “The Building”, replace this text:

As a Daily Action, if the Building is not Collapsed,

with this text:

As a Daily Action, if the Building is not Collapsed, and there is no Demolition that is Open,

In the rule “The Building”, add a subrule named “Block Numbers” and give it the following text:

Blocks in the Building are numbered from left to right starting at the Level below the topmost Level, then continuing left-to-right on the Level below, until the rightmost Block is numbered on the bottommost Level. The numbering begins with 1 and continues with the next Natural number. This number for each Block is the Block Number.

The number of Blocks in the Building not counting the Blocks in the topmost Level is called the Structure.

Add a new rule named “Demolition” and give it the following text:

A Demolition is a type of Event. The Creation Conditions for a Demolition are the following:
* There must be no other Demolition that is Open
* The Building Stability must be 100 or less
* The Engineer creating the Demolition must meet the criteria for performing a Build
* It has been at least 48 hours since the Engineer creating the Demolition created a prior Demolition,unless this is the Engineer’s first creation of a Demolition

The Response Format for a Demolition is a comment that satisfies all of the following conditions:
* The comment contains the phrase “I wager X”, where X is a number between 1 and the Structure
* The Engineer posting the comment has at least X Safety Checks
* The X in this Response is larger than the X in the most recent valid Response, unless this is the first valid Response

The Ending Condition for a Demolition is that it has been at least 48 hours since the Demolition was created.

The Ending Action for a Demolition is an atomic action with the following steps, which must be performed by the Engineer who posted the most recent valid Response. In these steps, the Engineer with the most recent valid Response is the Demolisher, and the value of X in their most recent Response is the Boom:
* If there are not at least 2 different Engineers who have posted valid Responses in this Demolition, skip the remaining steps and end the Demolition. Otherwise, perform the two sub-steps below Boom times or until the Building is Collapsed, whichever comes first.
* * Roll DICEN, where N is the current Structure
* * Replace the Block corresponding to the Block Number with an Empty Block, unless the Block is already an Empty Block
* If the Building is not Collapsed, the Demolisher adds the value of Boom to their Safety Checks. Otherwise, they add the value of Boom to their Accidents.

If this text is in the rule “The Building”:

If no Build action has occurred in the previous 48 hours, then any Engineer can Move On.

replace it with this text:

If no Build action has occurred in the previous 48 hours, and there is no Demolition that is Open, then any Engineer can Move On.