Halo: Combat Evolved/Vehicles

Scorpion
It is a slow-moving all-terrain tank. It has three weapons. The main one is the tank's turret: this fires an explosive round that does major damage, and works well against Banshees, Warthogs, other Scorpions, and pretty much any other vehicle (if you can keep them in your sights). The second gun is the machine gun mounted on the right of the tank. Use this for smaller targets, and in-between reloading turret rounds. The third are the treads. They basically run over everything, but don't use them as a primary weapon as the tank moves very slowly. If you stop and let Marines get on, they will shoot at everything at which they can aim. All weapons on the Scorpion have unlimited ammunition.

Using Scorpions
This is the easy part. The tank is very powerful (The cannon will destroy most enemy vehicles with even a glancing blow), and the machine gun works like an Assault Rifle on steroids. It is rather slow however, so don't plan on splattering anyone with it unless you've cornered them. Good news is that the tank will kill with even a glancing blow from a single tread. Here's how best to use it against the different opponents in multiplayer (these also work against AI's in Campaign)
 * Enemy's on foot: Shot them with the machine gun or blast them with the cannon. Just be careful if they have a rocket launcher or a FRG, if you are playing on PC, and if they throw plasma grenades.
 * Ghosts: Use that gigantic cannon to blast them to bits. You don't even have to hit them squarely, the blast will kill them if you miss. If you do miss, use the machine gun till the main cannon reloads. The MG wont destroy the vehicle, but it might kill the driver. At least it will make them move around to dodge your shots, which will reduce their accuracy.
 * Warthog (Normal): Same tactic as above.
 * Warthog (Rocket): Don't even bother with the Machine Gun if you miss. Just move around and dodge the rockets till your main gun reloads
 * Wraith (In Campaign): Blast them with the cannon and dodge their shots if you miss.
 * Banshee (In Campaign/PC): Use the machine gun to try and shot them down. Your cannon reloads to slow to make any difference. If they come at your head on however, you can try and use it. One hit and they're history.
 * Other Scorpions: Just dodge and fire back with both weapons.

Battling Scorpions
There are a couple of good ways to combat an enemy in a Scorpion tank:
 * The, hopefully, obvious way is to use a rocket launcher (or a FRG, if you are playing on PC) against an enemy Scorpion. Keep in mind however, that although tanks may drive slowly, you will still need to lead your shot to some extent, especially when firing from a long distance. One direct hit should kill under normal slayer rules.
 * If you can't get your hands on a rocket launcher, then probably an equally, if not better way, is to use a sniper rifle. There are gaps in the rollcage for the Scorpion, and so you should be able to hit the driver, if not score a headshot. Remember that experienced players will know better than to drive straight at you though, and will try to keep only their turret faced towards you, with the actual chassis of the tank facing the opposite direction.
 * If you wind up close to an enemy tank, try to use plasma grenades to destroy it, if you have them. You should only require two if you make direct latches, and if you don't have plasma grenades, throwing frag grenades under the tank will also do a fair amount of damage, but not as much as stickies would.
 * Another good way to take out an enemy tank is to use a Ghost vehicle. Because of the vehicle's stunning effect, the driver won't be able to turn as fast as he'd like, and so is rendered helpless as long as you don't overstrafe back into his turret's way. Also, even if that happens, it is considerably harder to kill a Ghost than another vehicle because of the fact that it hovers above the ground.
 * PC only: Should you wind up very close to an enemy Scorpion, then it is quite easy to just roast him with the flamethrower, provided you watch your step.
 * PC only: Also, you may use a Banshee to attack an enemy Scorpion in a fashion similar to that of the Ghost. However, keep in mind that you have a fuel rod cannon, which you can cause a large amount of damage with, but also, you have to fly out of the way, for the Banshee cannot strafe. Also, the Scorpion's turret has a maximum vertical angle.  Because the banshee can maintain a position directly above the scorpion and fire downward, this technique is one of the Banshee's most effective.  However, staying stationary above the Scorpion makes one easier to get hit by other vehicles.

These aren't the only ways you can go about taking down an enemy tank, but rather, they are just tried-and-true methods for combating these massive vehicles.

Warthog
Also known as the M12 light reconnaissance vehicle, the Warthog is standard to the UEG armed forces. The Warthog is fast and maneuverable, but can easily roll over during hard turns. Mounted to the rear of the vehicle is a three-barrelled machine gun, or in PC multiplayer, a three-barrelled rocket launcher.

Using warthogs
Driving a warthog is a piece of cake as long as you can detect patterns in your opponent's opposition style and you don't make hard turns.


 * A driver and gunner combination in a warthog can mean an incredibly effective drive-by solution, also a great distraction to the opposing team giving your team members time to move into the base and get the flag.
 * Warthogs can be stationed (sometimes with a gunner) in many places to creatively ambush the opposing team.
 * A rocket warthog on the hill behind the red base or the catwalk before the red base in Blood Gulch can deal many kills to the opposing team and, if done with precaution, can leave them confused for a while.
 * A warthog placed in front of the cave entrance to a base in Danger Canyon can be used to stop the opposing team from using it to get to the base and take the flag.
 * Warthogs stationed directly above a teleporter can sabotage it's team's ability to use it, requiring that they walk on foot to the teleporter site and unblock it. Until the vehicle respawns or it otherwise becomes unblocked with an explosive projectile, this can serve as a good way to attract the team to the teleporter and ambush them.
 * On the blood gulch map, and to a lesser extent on Ice Fields and Death Island, the Warthog can block the entrance to the flag, forming an easy defensive barrier that is nearly impossible to dislodge from the outside. Its critical that the front of the warthog is lodged at the inside of the base, so that it can only be removed by the defenders, and not by the attackers.  Notably, the Warthogs will eventually respawn at their default locations if unused, so it may be in the interest of the defenders to periodically enter and exit the vehicle to prevent the respawn.

Battling warthogs

 * Considered cheap if overused, many players will try to ram you over with a warthog when you're on foot. You can use this to your advantage by fooling the driver to get close enough to stick with a plasma grenade. If you have a plasma grenade and a warthog is approaching you in a predictable way, initially you'll want to appear to the driver of the warthog that you're helpless and unable to fight back by standing still. It'll appear to the driver that you're an easy kill, but in reality you've got a plasma grenade equipped and waiting to project. Once you're positive the driver has taken the bait and is about to ram you over, jump out of the way and stick the front of the warthog while you're airborne. If stuck at the edge of the warthog, you're guaranteed the warthog will flip over. If stuck near enough to the driver's seat, you may be awarded an instant kill in addition to knocking the warthog off it's path. However, this technique can be easily countered where more experienced players can whip you with the warthog's rear, making the odds of sticking the warthog lower and their odds of killing you higher. Furthermore, the driver might exit the warthog as soon as it's stuck to avoid as much damage as possible, so it's best you identify your opponent's experience before you try this technique.
 * In the event you don't have a plasma grenade handy, you can try throwing a normal fragmentation grenade in the path of a warthog. If the aim and timing is right, the grenade will knock the warthog off it's wheels and possibly kill the driver and passengers if any of them are low on health. This takes a lot of practice, and in theory isn't as effective as a plasma grenade.
 * A rocket launch to the driver's seat can instantly kill the driver and deal a lot of damage to the passengers. Just keep in mind you probably don't want to do this if the warthog is nearby and you don't want to commit suicide.
 * Sniper rifles can be used to take out stationed gunners and drivers when hit in the body or head, sometimes even while the warthog is in motion!
 * Like the above technique, the analogous pistol and assault rifle can be used to take out a warthog on the run.
 * Probably the most interesting way to battle a warthog is in a warthog. Commonly known as "hog wars", the drivers must try to knock over the other hog by ramming into it's sides or front bumpers, and ramming the driver and passengers once they are forced on foot. Other times a hog war can consist of drivers and gunners, but it can be very challenging and usually doesn't last long.

Ghost
The Ghost is the standard reconnaissance and rapid attack vehicle of the Covenant. Th Ghost is mounted with a directed energy weapon capable of launching a bolt of super-heated plasma. The Ghost may be fast and maneuverable, but the driver doesn't have much protection from incoming fire.

Using ghosts
Ghosts are wonderfully useful vehicles when it comes to quick flag snatching as well as hit-and-run kills. Its projectiles have a stun effect capable of stopping players on foot and dealing death by plasma or death by ramming. Ghosts feature a hard-to-flip-over bearing of the ground on tight turns, leaving unmatched durability in comparison to a warthog.

In general, the advantage of the Ghost is in maneuverability and speed. The Ghost is oftentimes able to quickly outflank enemy positions, and can be one of the most useful weapons against Scorpions. The Ghost also is the best vehicle for capturing the enemy's flag, due to its maneuverability, speed, and capacity to dodge enemy fire.

Unlike Warthogs, the direction a Ghost can travel and the direction a Ghost is facing are not controlled by just the mouse; it is able to strafe.

Battling ghosts

 * Ghosts hover above the ground and are very maneuverable, making it a hard vehicle to stick with a plasma or frag grenade. However, since the driver has almost no bodily protection whatsoever, ghosts can be easy kills with medium- and long-range pistol foresight.
 * The ghost's stunning plasma projectiles can disable your ability to move whether or not you're on a vehicle. However, it takes a considerable amount of time for a ghost to change the direction it's facing (and firing) when it's not in swift motion. When on foot, move sideways towards the opposite direction the stun gun is shooting toward. This will forcibly cause the ghost's driver to change firing direction, giving you more time to fire at the driver (preferably with a pistol.) Eventually, the driver will become frustrated at the slow response times and move around more or ram you over, leaving you with two options. One, take cover in a place a ghost cannot fit in and throw grenades out the opening, or two, throw grenades and fire back subsequently in hope of killing the driver. If you picked the latter, remember to hit the body and not the ghost, as hitting the ghost deals less damage than hitting the body.
 * The rocket launcher can do wonders in the event the driver of the ghost is nearby. A shot to the ground the ghost is hovering over or a shot directly to the ghost virtually guarantees a kill.
 * PC Only: An FRG can be used to knock a ghost off it's balance and force it's driver on foot, creating an opportunity to fight a fair and equal distance battle. But if you're low on health, you have the option of firing another fuel rod after the driver has fallen for a kill.

Banshee
The Banshee is the standard ground assault aircraft of the Covenants. The Banshee is very fast and maneuverable, with the capability of hovering. It has two weapon pods mounted on both sides of the fuselage, within these pods, a light plasma cannon and a fuel rod cannon are mounted. Only heavy weapons are capable of causing damage or destroying the Banshee.

Using the Banshee
Because Banshees have an aerial advantage, they are excellent against humans and vehicles alike. The fuel-rod cannon makes it a convenient tank-buster, and must be piloted in the Assault on the Control Room against the Wraiths. Like the Ghost, the plasma has a stunning effect, allowing you to mow them down more efficiently. Be very careful when approaching players in tanks, warthogs, or players that have heavy weapons.

Battling the Banshee
Since Banshees are aerial vehicles, they are harder to take down. Some tips, though:
 * Dogfighting. Chase after them on another Banshee. If two dogfighting Banshee's are in a remote area, the most natural action for both the pilots will be to encircle each other, each trying to take sharper turns and lead their opponent with an FRG shot.  Because FRG shots are impacted by gravity, in a dogfight one should always try to stay above their opponent.  If one intends to continue circling their enemy (as leaving the circle puts the enemy on your tail), the best strategy is to continuously try to take a harder turn then one's opponent, and lead them with FRG shots.  If there are allied vehicles or infantry in the area, sometimes the best strategy is to try to   take a hard turn and retreat from the site, allowing allied guns to attack the Banshee.  If your allies are armed with gattling guns, or have turrets manned, this is usually the best strategy.
 * If they are flying close to the ground, a plasma grenade will do the trick.
 * Rocket launcher or fuel rod gun. However, they may be hard to hit because of their maneuverability. Many Banshee pilots will be opportunistic and try to run over infantry.  If you have a rocket or a plasma grenade, don't have it armed or the Banshee pilot will try to take you from a distance.
 * The Scorpion. Barrage it with a machine gun and then fire a rocket just ahead of the Banshee.
 * The Warthog turret. The rocket turret is rarely, if ever effective against Banshees, unless at an extremely close distances, and at long distances the Banshee will be impossible to hit. On the contrary, the gattling gun on the warthog is probably the best way to fight Banshees.