A recent forum thread asked a simple yet highly debatable question: What's the best video game of all time?

There was much discussion, and many great games were considered. No consensus was reached, but because this is Marco.org and I'm Marco, I figured I'd declare one game as the winner based solely on my opinion.

Best Game of All Time: Tetris.

Tetris is the universal "game". No platform is considered worthy of gaming unless Tetris is available for it, and it's the first game widely played on most new graphing calculators, cellular phones, and PDAs. It completely defined portable gaming as we know it, starting with the original Game Boy version. Tetris is suitable for many situations, from occupying yourself while waiting on line at the bank to projecting a game onto the side of a building, visible for miles. It's almost as easy to program as it is to play, often being recommended as the first project for wannabe game developers.

Tetris is extremely accessible, with many fans and frequent players who never play any other games. I'd bet that more people know how to play Tetris than Solitaire. It never gets old, and it's never frustrating enough to discourage you from playing again. It has successfully penetrated untouched and unsaturated gaming demographics with ease, such as women and old people.

Multiplayer is completely open-ended - it's fun with any number of people, from one to seven (see the excellent TetriNet). The specific multiplayer mechanics can be customized and tweaked in many ways.

Tetris has also spawned an entire genre of its clones, called "puzzle games" by many publishers who don't have the license to say, "This game is sorta like Tetris." It's the defining puzzle game, the same way that 2D platform games can often be described as "like Mario." Many successful franchises, such as Columns, Dr. Mario, the underappreciated Dr. Robotnik's Mean Bean Machine, and the more recent Bejewelled are based on minor modifications of Tetris.

More importantly, unlike many other games considered for this honor, Tetris has seemingly endless replay value. New versions of Tetris with minor additions are always worth trying, and most players can pick up the original NES version and have just as much fun playing a few rounds as they did when it was released over a decade ago. That's incredibly rare in the gaming industry - can you find any game released in the last 5 years that will be just as fun to play in 2014 as it was on its release date, without seeming old and stale?

I hereby give Tetris the honor of Best Game of All Time. There's really no contest.