World 8-3 (Super Mario Bros.)
World 8-3 is the third level of World 8 in Super Mario Bros. and the thirty-first level and penultimate overall in said game. It is notably the only third level of a world in the game to not be of the athletic level type, meaning it isn't based around jumping from high platforms over pits. Instead, this is a mostly-flat overworld level taking place within the final castle's exterior walls.
The player begins in front of a Turtle Cannon, which is followed by a Koopa Paratroopa, another Turtle Cannon and a pipe with a Piranha Plant. After the pipe is a duo of Hammer Brothers that jump between two rows of Brick Blocks, and in the second to the right block of the top row is a power-up. After a small staircase, a Turtle Cannon, a Koopa Paratroopa, and some stone pillars is another Hammer Brother duo, and in the second to the left block of the top row of Brick Blocks is another power-up. Beyond a pipe is a row of Hammer Brothers, and at the end of the last castle wall is a hidden Coin Block (which is in plain sight in the Super Mario All-Stars version of the level). After some small Hard Block platforms is the flagpole.
Super Mario Bros. Deluxe challenges
In Super Mario Bros. Deluxe, the player can collect five Red Coins, find a hidden Yoshi Egg, and get a medal based on their score. The Yoshi Egg is found in a Hidden Block directly above the left of the castle decal after the second set of Hammer Brothers, and the score to beat is 28000. The Red Coin locations are: