Metal Slug X: Super Vehicle-001 (Neo Geo)

Metal Slug X: Super Vehicle-001
Developer: Nazca Publisher: SNK Platforms: Neo Geo, Arcade (Neo Geo) Released in JP: March 19, 1999 (MVS), May 27, 1999 (AES) Released in US: May 27, 1999 Released in EU: May 27, 1999 This game has unused areas. This game has unused graphics. This game has debugging material. This game has a hidden sound test. This game has a hidden level select. This game has regional differences. This game has anti-piracy features.

Metal Slug X is like the director's cut of Metal Slug 2, seemingly built from an early version of Metal Slug 3. The bombastic announcer makes its debut (RAWKET LAUNCHA!), and best of all, there are no more slowdowns! It's amazing.

To do: Sub-page for unused enemies and other objects. Some can be seen in the debug tests, however, there is much more stuff, as demonstrated by these hack ROM videos: [1] [2] [3] [4] Find a way to access them by code cheating or ROM hacking. Also add unused graphics from here: [5]

Sub-Page

Unused Stages A whopping 56 of them, in various stages of completion.

Debug Menu

おしながき

• メニューを　とじる（ＰＡＵＳＥしたまま） - Close the Menu (While Paused)
• ＳＥＴ　ＤＥＢＵＧ　ＤＩＰ
• ステージ　セレクト - Stage Select
• ＴＥＳＴ　ＳＴＡＧＥ
• サウンド　テスト - Sound Test
• ＣＯＬＯＲ　ＢＡＲ

It is worth noting this Debug menu is shared by Metal Slug 2, X, 3, 4, and 5.

To access the debug mode, open the game in Console Mode and set debug developer mode On at the Neo Geo boot-up screen: this can be done via the Kawaks emulator, the Nebula emulator or using the Neo Geo UniBios.

Enter the game, and press COIN twice during gameplay: after pausing, the debug menu will appear - with options to activate the debug dipswitches (which can be activated separately through other options using Kawaks) and even the ability to play on any regular level, and even some test levels not available in the actual game. There is also a Sound Test screen and Color Test screen.

(Source: http://randomhoohaas.flyingomelette.com/msmia/debug/)

SET DEBUG DIP

• ムテキ - Invincibility.
• ＶＩＥＷ　ＩＮＦＯＲＭＡＴＩＯＮ - View debug information.
• イツデモＰＡＵＳＥ - Allows pausing during score tally, cutscenes, and credits.
• ＶＩＥＷ　ＧＥＯ　ＳＣＲＯＬＬ　Ａ - 1st plane check, shows the walkable ground, makes the foreground choppy as it scrolls when activated. May linger if not turned off properly.
• ＶＩＥＷ　ＧＥＯ　ＳＣＲＯＬＬ Ｂ - 2nd plane check, makes the background choppy as it scrolls when activated.
• ＶＩＥＷ　ＡＴＴＡＣＫ　ＲＥＣＴ - View attack hitbox.
• ＶＩＥＷ　ＢＯＤＹ　ＲＥＣＴ - View body hitbox.
• ムセイゲン　グレネード - Infinite grenades.
• ムセイゲン　ＰＯＷガン - Infinite ammunition.
• ＶＩＥＷ　ＰＡ　ポイント - A sprite of Satiko Suzuki with the wrong palette appears, showing the player's respawn point.
• Ｄボタン、テキ　ゼンメツ - Press D to destroy all on-screen enemies (no score bonuses).

• 

  VIEW INFOMATION active, note the "ZOMBIE".

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  VIEW ATTACK RECT and VIEW BODY RECT active.

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  VIEW GEO SCROLL A, VIEW ATTACK RECT and VIEW BODY RECT active.

Stage Select

Exactly what it says on the tin, allows you to warp to all stages and sections in the game. Unlike Metal Slug 2, Metal Slug X contains a whopping 56 unused stages. Some of them were later used for Metal Slug 3 with major/minor spit and polish. See the sub-page on where does it warp to.

TEST STAGE

These strange test stages can be accessed with the above debug menu. While some of the test stages' names are the same as those of Metal Slug 2, they were completely different. There's also a couple of new names in the test stage selection.

• ＴＥＳＴ１　ｆｏｒ　ＡＮＤＹ　ＴＨＥ　ＷＩＺＡＲＤ The start of Mission 1, claims that it's Mission 3. There's a POW with an Armor Piercer at the start, and another AP, followed by boxes of Shotgun, Rocket Launcher, Flame Shot, Laser and Enemy Chaser. A Girida-O is parachuted in right after the Enemy Chaser, and the rest of the test level is empty.
• ＴＥＳＴ２　ｆｏｒ　ＭＥＥＨＥＲ will bring you to the start of Mission 4. The first thing you will see here is a rocket flying ass-backward (!) and a Camel Slug. Some mummy dogs and a runaway camel show up. Level doesn't scroll when the dogs are gone.
• ＴＥＳＴ３　ｆｏｒ　ＹＯＫＯ－ＳＨＵ transports you to the start of Mission 3, but it claims to be Mission 5. Parts of the game's credit bizarrely scrolls up immediately after you spawn. The two sunbathing soldiers can be shot dead, who will drop a shotgun and a machine gun if shot some more. A Metal Slug is available ahead, and lots of those guardposts in Metal Slug shows up, some are bizarrely floating on air. A rocket well is right up ahead, and two Dararin Dara Daras can be seen (the first one is dumping steel beams to the ground, should the player didn't advance too fast). After the frogmen up ahead, the houses can still be destroyed for food items like the original levels. When reaching the boss area, the screen scrolls slowly as if encountering the boss, but the boss never shows up.
• ＴＥＳＴ４　ｆｏｒ　ナミひら (Namihira) starts off at a section of Final Mission, with an MH-6J Masknell flying in, and unlimited Slugnoids to the right. Some soldiers show up, and getting to the end of the stage will end the mission and brings you to the total score tally and straight to the credits.
• ＴＥＳＴ５　ｆｏｒ　アリタ (Arita) starts you off at the start of Mission 1, but swordsmen Arabs show up instead of enemy infantry. A group of coins may or may not appear, and later on the stage, a coin, a banana or a steaming pile will spawn out of nowhere for grabs.
• ＴＥＳＴ６　ｆｏｒ　ＮＩＳＨＩＮＯ is Mission 4 claimed as Mission 2. Various armaments will be available at the start of spawn and things get weird from there. There are various enemies that would later appear in Metal Slug 3, such as the snail, the piranha, the foremen with plungers and the Japanese airplanes on ziplines. Like the YOKO-SHU test stage, upon reaching the boss area the screen scrolls slowly like when encountering the boss, but the boss never shows up.
• ＴＥＳＴ７　ｆｏｒ　ＮＡＫＡＴＵＫＡ it's simply a Mission 1 claiming that it's Mission 3. There is no music, no props to jump on (e.g. the first building you see) like the original stage. Getting to the building with the three towers, you will fight Morden in a chopper. Taking him out will end the mission and continues off to the proper game, Mission 4 and beyond.
• ＴＥＳＴ８　ｆｏｒ　ＴＡＧＵＣＨＩ is a section of Mission 2 claiming that it's Mission 4. There is a Slug Flyer at the beginning with a few mortar infantries. As you go up, various crabs will spawn from out of nowhere, and as you reach the last leg before the boss area, various coins, and mummy jars will spawn out of thin air. Like the YOKO-SHU and NISHINO test stage, upon reaching the boss area the screen scrolls slowly like when encountering the boss, but the boss never shows up.

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  TEST1 for ANDY THE WIZARD

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  TEST2 for MEEHER

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  TEST3 for YOKO-SHU

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  TEST4 for ナミひら (Namihira)

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  TEST5 for アリタ (Arita)

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  TEST6 for NISHINO

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  TEST7 for NAKATSUKA

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  TEST8 for TAGUCHI

Sound Test

SFX and BGM test screen.

COLOR BAR

Color test screen.

Region-exclusive Messages

Depending on what BIOS is used, the message shown at startup will be different.

US (MVS)	Japan

Note the misspelling "ADVISOLY". Also, the credit amounts are showed in the screen, which is unusual.

Anti-Piracy

To do: More technical analysis welcome!

Metal Slug X uses a unique PROG board, PROGEOP, only used by this game, featuring an Altera CPLD and custom Toshiba "0103" chip for protection purposes, running a constantly running stream of challenge/response. Should the responses ever be wrong or out of sync, then the game prints an angry red message to the screen and hard locks.

Of note is that current emulator solutions like MAME don't successfully emulate this protection, in favor of patching it out in memory!

(Source: Neo Geo Dev Wiki)