A glitch in level 1-2 of the original Super Mario Bros allows you to take the warp pipes to World 0-1 and this is the level you get! It is basically a Bowser castle but underwater. The rub is that if you go the wrong way, you cannot back track and will have to reset (press F5).
Best Browser Games
Goodgame Empire GameGoodgame Empire is a great strategy title. Build your own castle, create a powerful army and fight epic player versus player battles on a dynamic world map.
Goodgame Big Farm GameUsing business skills and the help of your neighbors, family and friends you can turn the overgrown barnyard into a beautiful and prosperous farm.
Empire: World War 3 GameBuild up your base, train your units, and command them in action packed battles. Observe your enemies' every move on the world map and loot their bases.
Goodgame Poker GameGoodgame Poker combines all the strategy, skill and excitement of Texas Hold’em with customisable avatars and a fresh and modern style.
Battle Pirates GameBuild an island fortress, customize deadly ships, and rule the high seas in the most epic MMORTS available in browser.
Shakes & Fidget GameSurvive exciting adventures in creepy dungeons or the mystical fairy tale tower, and defeat real players in the arena.