Create a rule entitled Mood.

  There exists a GNDT field named “Mood”, in which Gostaks’ Moods are tracked.

Every value allowed for the Mood of a Gostak falls on a scale from happiest to unhappiest.  The only values allowed, in order from happiest to unhappiest, are the following: Ecstatic, Happy, Content, Unhappy, and Depressed.

New Gostaks start out Content. A Gostak may change the Mood of one other Gostak often by one value toward Ecstatic or by one value toward Depressed.

Unless any other rule alters this, no Gostak may change eir own Mood.

Create a GNDT field named “Mood”.

Set all Gostaks’ Mood to Content.

Create a rule entitled Movement.

Gostaks may move between floors in a variety of ways. Any method of movement used by Gostaks must be listed in this rule.

*When a Gostak’s Mood is Ecstatic, that Gostak is immediately moved to the floor directly above the one e is currently on, unless e is on the 14th Floor, in which case e is moved to the 12th Floor, or e is on the 1st floor, in which case nothing happens.
*When a Gostak’s Mood is Depressed, that Gostak is immediately moved to the floor directly below the one e is currently on, unless e is on the 12th Floor, in which case e is moved to the 14th Floor, or e is on the 20th floor, in which case nothing happens.
*Any Gostak on the 16th to 19th Floor, inclusive, may move down one floor at any time.

Add the following to the end of the first paragraph of the rule “The Building”:

Floors may be referred to simply by their ordinal floor number followed by the word “Floor” (e.g. 20th Floor).