Alex World is a game you should absolutely attempt if you like Mario games and wish to challenge many different characters. The game is based on Super Mario, and your goal is to help the character Alex conquer his own universe by completing all of its stages.
Along the route, you must collect coins and break gold blocks. Jump on top of creatures like brown ones and snails to get rid of them because striking them directly means losing a life. Move and jump with WAD or ARROW, and shoot with Z when you have enough strength, which you can get by collecting potions along the way. Some potions make you bigger, while others offer you more lives or other abilities. If you lose all of your life, you will lose the game. Make sure you reach the flag at the end of each level before the time runs out.
Use the WAD, ARROWS, Z keys.