Castle Dash is an e-Reader level for Super Mario Advance 4: Super Mario Bros. 3. This card was released in Series 2 in Japan. Its official difficulty rating is ★★★★★. It was initially released only in Japan due to the e-Reader being discontinued internationally, although the level eventually became available overseas when the game was released on the Wii U Virtual Console in 2016. It is the 21st level of the World-e. It has five Advance Coins, and the time starts at 60 seconds. The key art featured Morton Koopa Jr.
The level starts with seven Boost Blocks moving the player automatically, giving an extra boost. There will be a series of eight Thwomps trying to catch the player, each two positioned a block more down. Before the other four the next conveyor belt will be in reverse, making difficult the player to avoid Thwomps. Then, the player must perform a high jump to get to the next platform. There will be another conveyor belt in reverse, then the player performs a high jump and continue to run to avoid the pit that is next to. Right on, there will be another Thwomp and another conveyor belt pointing to right. There are Boos and the first Advance Coin in mid-level.
The second area starts with a few Boos and a few walls. The player must jump when in the conveyor belt to nab the second Advance Coin. After, there are few Triangular Blocks, needed to get the third Advance Coin. After, there is a series of platforms where lies the fourth Advance Coin. The player has to get a perfect timing on the third platform to get the coin, due one tile gaps between platforms unallowing jumps.
The last area contains Spiky Balls which makes the player lose a life even if they are powered up, no enemies, few coins, and the last Advance Coin. The player has to do tricky jumps to avoid the Spiky Balls and get the last Advance Coin. Near the end there will be a lone Brick Block containing a 1-Up Mushroom, and Triangular Blocks. Now, the player has the remaining time to get out from the last area and getting the panel to exit the level.
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