Mario Bros.: The Underground

Mario Bros.: The Underground is the sequel to the NES classic Mario Bros., in which you bump the platform underneath the enemy to knock them out. The game debuted Luigi into the mix, which most would say is an absolutely great thing. This game too introduces a new character, as well as the Mario Bros. themselves and a few other characters from the series that didn't appear in the first Mario Bros.

Gameplay
The gameplay is basically the same as the first. Jump underneath the platform the enemy is standing on to flip them over, jump on top and run into them. This time on the other hand you can also use Melee attacks (punching, kicking, uppercut, etc.) to take out your foes. Once you wipe out all the enemies, you move onto the next level.

Mario
Combat Type: All-Around

Unlocked By: Doing Nothing; default character

Luigi
CT: All-Around

UB: Freeing him from Hookbill the Koopa in World 1

Wario
CT: Power

UB: Freeing him from Giga Lakitu in World 2

Yoshi
CT: Speed

UB: Freeing him from Buzzy Behemoth in World 3

Toad
CT: Speed

UB: Freeing him from Clawgrip in World 4

Waluigi
CT: Tricky

UB: Freeing him from Bugaboom in World 5

Shadow Mario
CT: Tricky

UB: Freeing him from Fryguy in World 6

Celio
Special Note: This is a new character

CT: Power

UB: Freeing him from Baron Brr in World 7

Mr. Mushly
Mr. Mushly was hired by the Mario Bros. to take care of their plumbing business when they went off to stop Bowser. Realizing that the situation was underground, Mario revisited his old friend so he could bring him underground to stop the reported menace. Mr. Mushly maintains contact via walkie-talkie with Mario upon his exploration of the infested sewers.

Princess Peach
Princess Peach is actually a minor nonplayable character in Mario Bros.: The Underground. She's mentioned by a Toad saying that "Princess Peach has news!" and seen when Mario goes to recieve them. Peach is the one who sends Mario underground.

Toadsworth
Toadsworth is seen with Peach whenever she is.

Hookbill the Koopa
From: Tetris Attack

Combat Type: All-Around

Giga Lakitu
From: Super Mario Galaxy 2

CT: Tricky

Buzzy Behemoth
F: New character to Mario Bros.:The Underground

CT: Speed

Clawgrip
F: Super Mario Bros. 2

CT: Power

Bugaboom
F: Super Mario Galaxy

CT: Tricky

Fryguy
F: Super Mario Bros. 2

CT: Speed

Baron Brr
F: Super Mario Galaxy

CT: All-Around

Wart

F: Super Mario Bros. 2

CT: Power

Goomboss
F: Super Mario 64 DS

CT: All-Around

General Guy
F: Paper Mario

CT: All-Around

King Bob-Omb
F: Super Mario 64 games

CT: Power

Kamek
F: Mainly Yoshi's Island Series

CT: Tricky

Army Hammer Bro
F: Super Princess Peach

CT: All-Around

King Boo
F: Luigi's Mansion and many Mario sports titles

CT: Tricky

Petey Pirahna
F: Super Mario Sunshine and many Mario sports titles

CT: Power

Enemies

 * Shellcreeper (arrives in World 1)
 * Spiny (World 2)
 * Buzzy Beetle (World 3)
 * Sidestepper (World 4)
 * Fighter Fly (World 5)
 * Fireball (World 6)
 * Freezie (World 7)
 * Koopa Troopa (World 8)
 * Goomba (World X1)
 * Shy Guy (World X2)
 * Bob-Omb (World X3)
 * Magikoopa (World X4)
 * Hammer Bro (World X5)
 * Boo (World X6)
 * Petey Pirahna (World X7)
 * Dry Bowser (World X8)

Story
The story begins with Mario going to his mailbox. He's aware that Luigi went on a quest to the sewers to take out a monster, and is sure he'll return. Mario gets the mail and comically says in his Italian voice "Bill...Bill...Bill...What's-a this?" Mario finds a strange letter and opens it. The letter states:

Dear Mario, 

''We must notify you that your brother Luigi will not be returning from his quest into the sewers. He was captured by what we say several monsters. Strangely, Yoshi and Toad have gone missing, too. An old friend of yours has agreed to help you save them. He'll be here at the castle to pick you up. ''

Sincerely, Princess Peach

Of course, Mario goes to the castle to see Peach and Toadsworth waiting there. Peach gives Mario further information and a map of the sewers. This map will serve as the map on the main screen in the game. Suddenly an old Blue toad with a long black moustache comes in and says that he's ready to bring Mario to the sewers.

In the truck, Mario and Mushly chat up a storm about the plumbing business. Mr. Mushly tells Mario how his old business is going under his own management. Mushly stops the truck and walks up to a manhole and tells Mario that this is the entrance to The Underground, the place where Mario had his adventures before. He warns Mario that the Underground has grown more dangerous but that it should be just as easy as last time because apparently Mario got stronger since the original Mario Bros.

Mario slips down the hole with the view still fixed on Mr. Mushly. Mr. Mushly realizes he forgot something and slips down the hole after him.

He's too late, though, and you see Mario being attacked by two Shellcreepers. A tutorial begins to introduce the different moves of Mario's. After the Shellcreepers are defeated, Mario is ambushed by many more. After the Shellcreepers are defeated, Mario discovers that the sewers have been jumbled into a maze. He must go through eight dungeons and defeat the monsters of each dungeon. He assumes that the other heroes that tried to go through the maze are in each of the dungeons too.

How does he discover this? He finds seven warp pipes blocked off by trapdoors that can only be opened with keys. A sign reads that the keys open up the pipes to the other dungeons.