Doki Doki Panic

Made by Shigeru Miyamoto in 1987 for the Famicom Disk System, Yume Kojo: Doki Doki Panic (or "Dream Factory: Heart-Pounding Panic") is the game that would later become Super Mario Bros. 2. Even though Shigeru Miyamoto was involved heavily in the game's development, he never really intended for this to be a Mario game. The reason why it became one is because Japan's SMB2, now known as Super Mario Bros.: The Lost Levels, was either deemed too hard for non-Japanese gamers, or too much of a clone. Unfortunately, Nintendo of America couldn't just sit on their asses all day and wait for Japan to develop another SMB2, since, in 1988, Nintendo already released Super Mario Bros 3 in Japan.

The story starts with two children that were reading a storybook when a hand suddenly grabs them and sucks them inside the book. The family of the twins discovered what happened thanks to the pet monkey and rush inside to save them. Sucked into the world of the storybook, the family will have to fight off several monsters across seven chapters: Imajin, the balanced one; Mama, a very high jumper; Lina, who can float for a few seconds; and Papa, who has the strongest throw.

Even though this is "not a Mario game", quite a few enemies from this game have gone on to star in future ones. In fact, Bob-Ombs would appear in the very next game and go on to become a series staple. Pokeys and Sparks would appear in Super Mario World, albeit with changed appearances (and in the latter's case, a changed name: "L'il Sparky"), and the former would also appear in Super Mario 64 and Super Mario Sunshine. Shy Guys would re-appear in Yoshi's Island, which takes place BEFORE this game in canon. Birdo would re-appear in a Wario game and has appeared in every Mario sports title since the original N64 version of Mario Tennis in 2000. Also, as late as Super Smash Bros Brawl, Princess Peach uses many abilities from this game, and this game is the Trope Codifier for Luigi's signature high jump and low traction (even though he had these things in Lost Levels).

Major differences between this game and Super Mario Bros. 2
Visual
 * Overall, the game had an Arabian theme.
 * The title screen in this game was a bit more lively, with balloons rising and popping the logo out. It even played a cutscene to show the story.
 * The worlds were called "chapters".
 * A golden lamp replaced the potion that produces a door to Subspace and the mushroom that grants you an extra hit point was originally a heart.
 * Very few sprites in this game (including, but not limited to, the cherries and POW blocks) are animated compared to those in SMB2, and even those that were didn't have as many frames of animation as the American version (for example, Albatoss only has a two-frame "flap" in DDP.)
 * The slot machine at the end of each level was very bland looking, but the vegetable icon changed to match the level's theme. Also, if the player had more than nine bonus coins, it was replaced with a letter (i.e. A for 10, B for 11, et cetera).
 * The tufts of grass were black. They're red in SMB2, but when you pull out a vegetable, it still has black leaves in the original NES.
 * Waterfalls rushed down much faster.
 * The Koopa shell was originally a blackface head.
 * Instead of mushrooms like in SMB2, you throw masks at later Birdos.
 * Bombs that went off went "BOM" instead of "BOMB" like in SMB2.

Audio
 * Being on the Famicom Disk System, DDP allowed more detailed sounds than SMB2.
 * Subspace plays an Arabian theme instead of the iconic Super Mario Bros. theme. Picking up a star also plays an Arabian theme.
 * At least two level themes were altered in SMB2. The "overworld" theme has an additional section not found in DDP, and the "underworld" theme was slowed slightly and given an additional "drum" part in SMB2.

Gameplay
 * You can save in DDP.
 * Once you selected your character, you had to commit to that character for the entire game. Each character represented a save file.
 * Getting down to 1 HP doesn't shrink you like in SMB2.
 * You can't hold down the B button to run.
 * When you get the key from Phanto's room, he doesn't pursue you until after you leave the room with the key. He also doesn't have the Nightmare Face that SMB2's Phanto has.
 * World 5-3 in this game features a third Mouser. He was replaced with Clawgrip in SMB2.
 * Worlds 7-1 and 7-2 are designed slightly differently.
 * Wart has less HP in DDP.

'Since this game and Super Mario Bros. 2'' are so similar, see that article. Any tropes listed below are exclusive to this game.'''
 * Action Mom: Mama, the Luigi Distaff Counterpart. MAMA? MAMA LUIGI?
 * Badass Family
 * Blackface: The sprite of what is now the Koopa Shell.
 * Meaningful Name: Imajin.
 * Portal Book
 * Shout-Out: Before it became a Mario game, it already had the POW block from the original Mario Bros., plus the coins, and Super Star from Super Mario Bros.
 * Trapped In Book Land