This game is not so much a word-building game as it is a word-stealing game.
You play by drawing a card to determine the category of word you’re looking for, and then rolling the dice. One of the dice is a “position” die. The others have letters.
Once the dice have been rolled, players shout out words that both match the category and have one of the letters in the position indicated by the position die. When you shout a word, you grab the die, stopping other people from using it. For example, if the category is “dessert”, and the position die indicates “2nd”, and one of the letters is “i”, you could shout out “pie” and grab the “i” die. At the end of each round, you get points according to the letters you collected.