OnDestroy Function ondestroyfn : Name of the function to use from already parsed .as script files when entity is destroyed (killed) in any way. If the function belongs to namespace, you must use prefix with the namespace name (e.g. mynamespace::MyFunction) for the keyvalue.

Name targetname : Set name of path_track so other entities can trigger it to enable or disable it or branch path. Depending on trigger use-type: 'On'- enable this path, 'Off'- disable this path, 'Toggle'- toggle this path. If "Branch Path" is specified: every time this path_track is disabled the one specified in branch path is used. Can be kill-targeted.

Pitch Yaw Roll (X Y Z) angles : Where Z means Y and Y means Z, that is, when you're thinking Hammer-grid. (Hammer uses Z for height and Y for depth, while every other sane 3D-application does this the other way round; nonetheless this keyvalue description has the letters in the conventional order) This, technically, is a 3D-vector containing Euler-angles to describe either the entity's rotation or direction of effect. E.g. a func_door_rotating will use this as its initial rotation, while a trigger_push will keep its original alignment and use this for the direction of its push-effect instead. Euler-angles are a hierarchical system to determine an object's orientation in 3D-space. A yaw-value of 0 would mean the entity would face east. (right in top-down view) 90 would mean it would face north. (up in top-down-view) After yaw, pitch is applied. Think aiming up/down with your character in first person. At last, the roll-value is applied. Think your character falling over sideways in first person. Some entities, mostly point entities, do not use the angles keyvalue for any purpose.

Next stop target target : Name of the next path_track to go after entity reach this path_track. Can be kill-targeted, any object heading this path_track will move toward map center coordinates.