Due to its high speed, and low protection provided to its operator, it is usually not the best idea to take one for use if heavy combat is to be expected. Instead, use it to speed from one point of conflict to another, hopping off as soon as combat begins. If, however, there happen to be Marines in the area, and you have a Rocket Launcher,there's a different story...
If the player is having difficulty using the Mongoose in The Storm, take a Marine's Rocket Launcher and let him drive. He will drive erratically, but he will probably be better than your weaving and unstable movement.
In Halo 3: ODST, look for supply caches unlocked by obtaining audio logs. These will appear as the Superintendent's avatar on your VISR'sNAV. Some of these supply caches contain Mongooses, which will greatly increase your travel speed and could turn 5 minutes of on-foot combat to one minute of cruising through the streets of New Mombasa.
Never use the mongoose for combat. It is weak and frail and lacks any form of offensive weaponry. Not recommended to drive offensively, unless you have a teammate with a power weapon, like the Rocket Launcher or Spartan Laser, though if your teammate has a Plasma Pistol it can become a powerful anti-tank weapon, assuming the driver can stay mobile enough to not be targeted.
Due to the high-speed and compact nature of the Mongoose, it is a very useful and effective vehicle for objective-based games, such as Capture the Flag or Assault. It is entirely possible in Assault for the attacking team for one player to drive a Mongoose while another player rides as the passenger with the bomb in-hand and rush the enemy base while the defenders are distracted for a quick plant. Similarly, a Mongoose with two players can get into an enemy base, snag the flag, and get out before the enemy know they are there. It is also possible to use the Mongoose for rapid tactical transportation as well, to relocate players to critical areas, to reach weapon spawns before opposing players, or to prevent enemies from scoring a flag.
As aforementioned, the Mongoose is extremely vulnerable to explosives of all kinds: grenades, or even the Brute Shot and Concussion Rifle can effortlessly flip over this low-mass vehicle, often times sending the rider tumbling to great heights or into walls.
It is advised to not go full-speed over hilly terrain due to the vehicle's high center of gravity and low weight, making it easy to flip or lose control.
The Mongoose is an obvious target for snipers and vehicle gunners, and, even at close range, players can easily disable the Mongoose with a charged plasma pistol shot or out-right kill the driver. Additionally, use of sufficient suppressive fire can be effective in killing the highly vulnerable operators.
On the map "Sandtrap", you can use this vehicle to drive through the minefield around the perimeter: its speed is great enough to outrace the mines triggered by the towers. While opponents are usually concentrating on the center of the map, two players can grab a Sniper Rifle or another power weapon by traversing the exterior of the map, and dipping in for the weapon. The only thing the player needs to remember is to keep driving no matter what.
Another advantage of the Mongoose is the weapon load out: a smart team can use one Mongoose to disable a Wraith, or Warthog with a plasma pistol, while a second or third Mongoose will use grenades against the downed vehicle, or will use some kind of anti-vehicle weapon. The rider can also hop out and board the enemy tank from close range. But one must not forget that an overcharged plasma pistol bolt can, and may shortly disable the player's vehicle too.
The Mongoose is the main vehicle used when a player makes a Forge race map: Because of the Mongoose's small size, the player can forge small quarters where any other vehicle wouldn't fit. For example, players can easily drive a Mongoose through an open container, while other vehicles might be more awkward or too large in such a space.
A Mongoose, coupled with a passenger carrying a heavy weapon and a Brute Shot or Concussion Rifle (depending on the game), can make the tiny vehicle a veritable force on the battlefield. Using the Brute Shot to make the Mongoose fly into enemy territory, allowing the driver and passenger to catch enemies off guard. With a power weapon, such as a Spartan Laser or a rocket launcher, the two could potentially take out any vehicles before they had the chance to get mobile. Offsetting this is the amount of skill required, as the Brute Shot grenades can often be detrimental if used improperly, and the Spartan Laser can be hard to operate in the passenger seat (especially with the lack of a zoom function due to being in a vehicle).
In Halo: Reach, it is possible to be the flag carrier while driving a Mongoose. The flag will just end up being holstered onto the player's SPARTAN's back, much like a normal weapon. This is the only vehicle so far to allow a player to carry the flag while driving it.
A good team tactic in CTF gametypes is to place the Mongoose on top of where the flag spawns. This is helpful because players may accidentally get into the Mongoose instead of grabbing the flag. The tactic can also be done with a Warthog, but since Warthogs have guns and can be used offensively, this is considered a waste. This is a small distraction that can easily be avoided by the other team by moving the Mongoose or by throwing a grenade and send it flying. It will, however, still cause a delay, letting your teams defenders have a better chance. Note, however, that if no one is there to take advantage of the lost time, this distraction will be nothing more than a free getaway vehicle back to their base. Additionally, the amount of time it takes to set up this defense can allow the enemy team time to close in and begin camping your base.
If the player finds themselves doing an out of control barrel roll on a Mongoose, pressing the jump button makes the Mongoose stop flipping and eventually land on its wheels. Do not get it mixed up for when you are sliding upside down in a Mongoose. This skill is highly effective in explosive games, such as Rocket Race. It also works effectively on bumpy maps like "Valhalla"/"Ragnarok" and "Hemorrhage"
With the strength of the M739 SAW combined with the large magazine size, the M739 can serve as a portable turret. While participating in game types such as Team Slayer or Capture the Flag in which vehicles are involved, a teammate can ride on the back of a Mongoose with the SAW; converting the Mongoose into a downsized Warthog. Another advantage to this method is the increased looking mobility which is twice than that of a Warthog turret.