Update:
Add filter document.
Advance: Filter
The filter feature could re-assign the target instances got by plugin in "action:Get moveable area".
Get move-able tile without any chess standing on it
For example, if designer want to get the move-able tile without any chess standing on it. Add "condition:On filter", and set the filter name into "action:Get moveable area". Use "action:Append filter result" to re-assign the captured UID of instance under "condition:On filter".
In this capx, call "action:Append filter result" only if (expression:TileX, expression:TileY, 1) is empty. So that the tiles with chess standing on it will not be selected.
BTW, the filter could not only select tile, but also could be used to select chess to get the chess target. For example, get the attacked targets.