If you are playing as Darth Maul, use Force Push to push any trooper into the trapdoor. As Aayla Secura go to the small side of the trapdoor, or if you want to do this in Star Wars Battlefront, you can ask one of your fellow troopers to follow you, then go to the trapdoor with your partner. If he's still following you and you're still in the Rancor Pit, go behind the Rancor and if it works he will be eaten. You can do the Barfing Rancor, as well. This can be done to a Gammorean Guard but you have to be a Jedi. You can use any force power to make the Gammorean get eaten, but if you want to force pull, go behind the Rancor and force pull. However, you can face the guard and if he tries to kill you go behind the Rancor and he might try to follow you and kill you.