There is a well-known bug in SL since version 1.8 and some people like to make a game of these kinds of things.
The Prim return game rules.
1. Your attack script must only attack one sim and it should be hard coded for that preview sim name to prevent it from getting away from you.
2. If you find an exploit, do NOT publish it. Bug report it!
3. You do NOT get any points for crashing the sim or the preview grid.
4. You can’t own land in the sim that is being attacked, but you can attack from another sim.
Points
1. One point for returning a prim on land where the existing prims are not owned by the owner or “set to group” for group land.
2. One more point if the land is “No build”
3. One more point if the land is “No script”
4. Two more points if the land has “auto return” turned on.
5. Ten points if the objects on the land are set to the group.
6. Twenty points if the returned objects are owned by the owner or are deeded to the group.
Notes:
1. Objects created in the preview grid are not saved!
2. You can create objects on the main grid and then use it on the preview grid. (Delay?)