Heres what you do, You get WorldGuard, or any region plugin, select 4 Walls, for example..
X--------Y
| |
Y--------X
Then claim each wall as a different name, then flag all the regions with passthrough
Example:
/rg flag pointX1 passthrough deny
When users try to walk inside the invisible wall, It will not let them, Perfect for Mini-Game Lobbies and whatever you need help with, Hope this helped!
-Epizoid
