Rules of KCG Yahtzee

Objective

The object of the game is to score the most points by rolling five dice to make certain combinations.

The game consists of 13 rounds. In each round, you roll the dice and then score the roll in one of 13 categories.
You may roll the dice up to three times on your turn.
On your first roll, you roll all five dice.
After the first and second rolls, you may choose to "hold" any number of dice and re-roll the remaining ones.
After three rolls, or when you decide to stop rolling, you must choose a category to score.
Each category can only be used once per game. If your roll does not fit any available category, you must choose one to "scratch", scoring zero points in it.
The game alternates between the human player and the computer opponent.
The game ends when both players have filled all 13 scoring categories. The player with the highest Grand Total wins.

Ones: The sum of the dice with the number 1.
Twos: The sum of the dice with the number 2.
Threes: The sum of the dice with the number 3.
Fours: The sum of the dice with the number 4.
Fives: The sum of the dice with the number 5.
Sixes: The sum of the dice with the number 6.
Bonus: If the total score of the Upper Section is 63 or more, you get a 35 point bonus.

Three of a Kind: At least three dice showing the same face. Score is the total of all five dice.
Four of a Kind: At least four dice showing the same face. Score is the total of all five dice.
Full House: Three of one number and two of another. Scores 25 points.
Small Straight: Four dice in a sequence (e.g., 1-2-3-4, 2-3-4-5, or 3-4-5-6). Scores 30 points.
Large Straight: Five dice in a sequence (e.g., 1-2-3-4-5 or 2-3-4-5-6). Scores 40 points.
Yahtzee: All five dice showing the same face. Scores 50 points.
Chance: Any combination. Score is the total of all five dice.