Shobon no Action, also known as Cat Mario, is a Japanese freeware platform game released in February 2007. The game features frustrating elements which has made it subject to internet video game commentary, such as ostensibly innocuous objects that kill the character in ways unforeseeable to the player. Though the game is a parody of Super Mario Bros. for the Nintendo Entertainment System, it adds elements from other Mario games such as Super Mario World.
The player controls a white kitten-like character who must venture through side-scrolling platform levels similar to Super Mario Bros. The game consists of four levels riddled with traps designed to trick the player, and abuse their previous knowledge of Super Mario Bros. gameplay, including normal-looking ground tiles that fall away into pits, blocks that sprout spikes when touched, a coin block at the start of a level that goes up when the players try to hit it, enemies that spawn nearly on top of the character, deadly background scenery, coin blocks rigged at the edge of a pit to cause the character to fall down, warp pipes flying, and a Mario-style flagpole that kills the character in two different ways, either by falling over or shooting a laser towards the player character. Despite the surprise factor of these traps, the levels do not change between plays, allowing the player to memorize their locations and patterns and eventually make progress. Some designers have commented on how the game requires the player to think logically through trial-and-error in order to complete the game at defeating the main antagonist called Onion King. The player has infinite lives.