Dr. Mario is an arcade puzzle game developed and published by Nintendo for the NES console in 1990. In the game, players control a character named Dr. Mario who throws colored capsules into rotating containers filled with viruses located at the bottom of the screen.

The goal of the game is to eliminate all the viruses on the screen by combining capsules with viruses of the same color. Players can rotate and move capsules to create vertical or horizontal lines of three or more capsules of the same color. Once a line of three or more capsules matches a virus of the same color, it disappears.

The game has several levels of difficulty, with the number of viruses increasing on each level, making the game more challenging. Players can choose the speed of capsule descent, set the game time, and select the number of viruses needed to win.

Dr. Mario has both single-player and multiplayer modes. In the multiplayer mode, two players can compete against each other to eliminate viruses. One player plays as Dr. Mario, while the other controls the speed of capsule descent and the number of viruses on the screen.

Overall, Dr. Mario is an addictive and exciting game that requires quick reflexes and good strategy. Players of any level can enjoy the game, thanks to its variety of difficulty levels and multiplayer mode.