Power Hour, with its variants Centurion

Centurion (game)

Centurion, also known as Century Club, Century Challenge, One-Hunzy-Hunzy, Chicken of the North, Hundred's Club and Century Clock in North America and the UK, is a drinking game. Although there are variations in the rules, a basic premise remains; drink one hundred shots of beer in as many minutes...

 (aka Century Club) and 21 for 21, is a drinking event where player(s) drink a specified number of alcohol shots within one hour. Variants include one shot of beer every minute for an hour or 21 shots within one hour.
In the USA, a power hour event is often associated with a person's 21st birthday when they reach the legal drinking age.

Health risks

The game's rules appear simple; however, players often have difficulty completing the specified number of drinks as the rate of consumption necessary to win many forms of this game can, depending on the player's weight and other factors, raise their blood alcohol content to high levels. The rate of alcohol consumption makes the players intoxicated within a short period of time.

Each shot of beer contains 1.5 fluid ounce

Fluid ounce

A fluid ounce is a unit of volume equal to about 28.4 mL in the imperial system or about 29.6 mL in the US system. The fluid ounce is distinct from the ounce, which measures mass...

s (US

United States customary units

United States customary units are a system of measurements commonly used in the United States. Many U.S. units are virtually identical to their imperial counterparts, but the U.S. customary system developed from English units used in the British Empire before the system of imperial units was...

) (44mL), for a total of 90 fl. oz.

Fluid ounce

A fluid ounce is a unit of volume equal to about 28.4 mL in the imperial system or about 29.6 mL in the US system. The fluid ounce is distinct from the ounce, which measures mass...

 (5.63 US pint

Pint

The pint is a unit of volume or capacity that was once used across much of Europe with values varying from state to state from less than half a litre to over one litre. Within continental Europe, the pint was replaced with the metric system during the nineteenth century...

s, 2.66 litres, or 4.68 Imperial units pints) of consumption during the power hour. For purposes of blood alcohol content

Blood alcohol content

Blood alcohol content , also called blood alcohol concentration, blood ethanol concentration, or blood alcohol level is most commonly used as a metric of alcohol intoxication for legal or medical purposes....

, this amount of beer is equivalent to 7.5 drinks. In the Centurion

Centurion (game)

Centurion, also known as Century Club, Century Challenge, One-Hunzy-Hunzy, Chicken of the North, Hundred's Club and Century Clock in North America and the UK, is a drinking game. Although there are variations in the rules, a basic premise remains; drink one hundred shots of beer in as many minutes...

 variant, beer shots are drunk one per minute for 100 minutes, with a shot size of 35mL, totaling 7.4 US pints (3.5 litres or 6.16 Imperial pints), or 9.9 drinks.
There are many difficult variants of Centurion, amongst them are Gladiator and Spartan. Gladiator is 200 shots of beer in 200 minutes, and Spartan is 300 shots in 300 minutes.

Trademark controversy

In 2010, Steve Roose, who markets a DVD game named "Power Hour", registered a trademark of the same name and soon after began sending cease-and-desist orders to Ali Spagnola, a musician who had released an album also entitled Power Hour. Spagnola has announced her intentions to fight the claims, and an intellectual-property professor from the University of Pittsburgh has stated that "if 'Power Hour' is a generic description of 'a drinking game that involves drinking a shot of alcohol each minute for an hour,' then Mr. Roose can't have any trademark rights at all."