The Tani Oh ("Valley King" in Japanese) is the third boss from Metal Slug: Super Vehicle-001.
The Tani Oh is a prototype heavy artillery tank, armed with two huge cannon capable of devastating large areas without much effort: these twin guns are possibly an experimental railgun, since their shots are instantaneous light bolts and the turret, instead of ejecting the expanded casings, discharges smoke and heat from the vents on its back. It is also equipped with two turrets on each side, both with a minigun and a mine launcher, to cover the tank in short range. Only one unit was produced, being used by the Rebels for testing purposes in the Käthehirt Valley.
The Tani Oh is a very simple, yet deadly boss. It moves in a lower platform compared to your character, so it will always be below you, forcing you to jump constantly (without the Metal Slug) to shoot at him. Its main weapon is its large double railguns, which not only covers a big area, but is also very fast. It also throws mines everywhere in your path and will sometimes use its miniguns to kill you. Having a Metal Slug while fighting the boss makes things a lot easier. Warning: If you blow up its two smaller turrets, it will constantly use its main laser turret, which goes a lot faster on it's own, making the battle a lot harder.
Also, while you're fighting Tani-Oh and choose to continue, instead of a Heavy Machine Gun appearing, it will be a Rocket Launcher, which only happens when fighting this boss.
- The Mammoth Tank from the popular Command & Conquer series bear a resemblance to the Tani Oh. The 4 independent treads and the dual cannons are the standout features. It also looks like a M2-Hydra from Battle Tanx Global Assault.
- The hull of the Tani Oh also resembles the up-armored variant of the Chinese Overlord tank in Command and Conquer: Generals - Zero Hour, the Emperor Overlord which is exclusively used by General Ta Hun Kwai of the Chinese People's Liberation Army (PLA).
- Tani Oh's early design was based on British Churchil I heavy tank.
- Another of Tani Oh's early design also based on British FV215b heavy tank prototype.
- Its name (谷 王) means "Valley King".
- Tani Oh is the only boss in the series that drops Rocket Launcher instead of Heavy Machine Gun when the players use a continue.
- Tani Oh's pilot appears in a Metal Slug Pachinko game, and is a girl. There is not much information about her, other than her affiliation with the Rebel Army.
- Tani Oh appears as a background boss in Metal Slug Defense in the Alaska stage in the world 6.
- In Metal Slug Attack Tani Oh is featured as the Monday-Tuesday boss in the Day Specific Mission.
- In Metal Slug Attack, Tani Oh has a special variant made for the Extra Ops: Santa Trap, where its main cannon and mine launcher is is facing on Horizontal. in-order for it to fire its cannons against the enemy units in front.