The Hi-Do is a transport gunship used by many factions.
The Hi-Do is a tandem rotor helicopter used by Donald Morden, which is also used in carrying VIPs. Designed for testing purposes, it has heavy armor and is equipped with several weapons, making it a versatile combat vessel. It is a modified version of the Orewana Ko-42h "The Keesi I" transport helicopter that was owned by the Russian Federation. .
It is the last boss from Metal Slug: Super Vehicle-001 and later appears in Metal Slug 3 as a mid-boss of the last mission used by a Mars Person masquerading as Morden. In Metal Slug 4, there is a blue variant that is used by the Regular Army to transport their commando units, likely a repurposed version of the original captured after the Rebel's defeat. There is also a longer green version that appears in Metal Slug 6, and another green version that appears during Metal Slug 7 credits, ridden by Rumi Aikawa. The Regular Army's variant of the Hi-Do is called the Regular Army Helicopter.
The overall armaments of the various Hi-Do models vary, both on-board and those carried by their passengers, but a nose-mounted missile launcher with three tubes is found in nearly all models.
As the Hi-Do is the personal transportation of General Morden, he himself appears on the cabinet, firing rockets from his bazooka constantly, in the same way he does from the Hairbuster Riberts. Morden is constantly aiming at the player and can fire in any direction except under or above. If the player stays under him too long, the minigun underneath will fire from right to left. Its main attack is to launch heat-seeking missiles from the front, and after some time, the Hi-Do will begin to carpet bomb the entire screen. The same attacks are used in a Metal Slug 3 mini-boss fight by a Mars Person disguised as Morden. The speed of its movement and attacks will begin to increase as its heath lowers.
|Hi-Do:The original, as ridden by Donald Morden himself.|
|Regular Army Helicopter: Variant used by the Regular Army in Metal Slug 4.|
|Hi-Do (Transport): Variant ridden by Rumi Aikawa in Metal Slug 7. It also found in the first scene of Mission 5 in Metal Slug 6, deploying both the player and Rebel Army soldiers against Invaders.|
|Hi-Do(Amadeus): Variant created by the Amadeus Syndicate in Metal Slug Attack, it looks just like the original model only painted purple and ridden by a Morden Robot.|
|Hi-Do MK II: Upgraded variant of the Rebel version now painted in red. It can also airdrop missiles that are capable of nullifying projectiles.|
|Hi-Do MK III: Upgraded variant of the Rebel version painted black and olive green, making it look similar to the original. The missiles it airdrops weakens the enemy's strength and can also seal off their attacks.|
|Abigail's Hi-Do: A custom-made Hi-Do used by Abigail. It is painted pink and brown for anticipation of Valentine's Day; as expected because of its prominent passenger, the hatch contains a custom-made laser sphere and launches highly advanced missiles with a chocolate sculpture of its passenger wrapped above it.|
- The Hi-Do is based on the CH-47 Chinook helicopter.
- Metal Slug Official Guidebook (1997), pg. 51.