Energy Trap
this was a form of protective defense that could be created by Dark Jedi and Sith practitioners. The energy trap was essentially a concentration of Dark Side energy that was nearly invisible to the naked eye. However, it could sometimes be discovered in a being's peripheral vision as a brief flash of deep color. When a Jedi Knight stumbled into an energy trap, they found themselves instantly immobilized, unable to move without tightening the trap. Only those Jedi Masters who managed to dedicate their complete concentration to escaping the trap could break free. Because of this, many Sith left energy traps just outside areas where they could ambush the Jedi, forcing a being that was trapped to choose between utter withdrawal or useless thrashing in order to break free.