This move can be used in any three to five dice game like Buck Dice, Poker Dice, Cubilette, etc., using any dice cup, including ribbed and tripped dice cups.  The cheat only controls the outcome of one of the dice, but this still gives him a significant advantage over the other honest players and he will win more games than the straight-playing dice players.

The cheat will move the mouth of the dice cup towards the dice set on the flat playing surface, and push each one into the cup using his two forefingers, as illustrated in Fig 1.  However, the last die isn't pushed into the cup, but is instead held by the forefingers, with the desired value face-up, against the lip/rim of the cup, concealed from the other players by the cheat's fingers, as illustrated in Fig 2.  Finally, the dice are thrown from the dice cup, but the held die is simply slid or set down as the rest are thrown, as shown in Fig 3.

A very simple and effective method of cheating with a dice cup, that can be very hard to spot if you don't know the methods of the technique.