Jacking is an Orcish term for carving up Halfings. Carving up Halflings is so popular in Orcish culture they even have a dice game for it called Jacked. The object is to carve up a halfing slowly to torture it to death by removing it's arms and legs.
To that end, you roll two six sided dice. only doubles count
66 = Head
55 = Chest
44 = Left Arm
33 = Right Arm
22 = Left Leg
11 = Right Leg
If you roll double fives or sixes, the halfling dies and you lose the game.
The twist: Orcs often capture halflings and play this game for real.
If you remove the limbs before the halfling dies and before everybody else, you win. If you successfully cut off a limb you get another roll.
Orcs often use this as a Gambling game as well.
If you hit the head and chest before you've cut off the limbs, you've lost the game.