Command And Conquer 64

Cheat mode:
Press B, A, R(2), A, C-Right, Up, Down, A at the title screen. Select the "Replay Mission" option at the main menu, then press L to display all missions and R to select your team.

Start battle after enabling the code. Press L + R to display programming debug information. Press R + L + Up to automatically win or R + L + Down to automatically lose.
Information in this section was contributed by Kagle Jackson.

Adjust battle screen:
Hold R press C-Up or C-Down to magnify and reduce the battle screen.
Information in this section was contributed by Andy Jardine.

Easier building:
Highlight a unit to be created from the toolbar, then press A. Hold Z and press A after receiving the "Unit Ready" or "Construction Complete" message to build the same unit again without returning to the toolbar.

Hint: Easier Tiberium harvesting:
To make the harvesting job quicker, run sand bags to the Tiberium and place a Refinery there. Then, sell the bags.
Information in this section was contributed by Luke Elliott.

Hidden message:
Remove all controllers, then turn on the Nintendo 64. Watch the opening images and text until it reaches the controller screen.
Information in this section was contributed by Adam Rutherford.

Hint: Build away from base:
To build away from your base, simply create a chain of sandbags to the desired location.
Information in this section was contributed by Andy Jardine.

To take over the enemy base, you can simply build sand bags directly into the enemy's base. Once you have you the sandbags in place, build Obelisks and destroy anything in the base that may be a threat to your engineers. After it is safe, simply make some engineers and send them into the enemy base.
Information in this section was contributed by General Vyper.

Hint: Use opponent's structures and men:
Use an engineer to get into your opponent's Mobile Construction Unit. This will allow use of your opponent's structures, men, and more.
Information in this section was contributed by Ron Koehler.

Hint: Faster training:
Build more than one Barrack or Hand Of NOD to increase the training speed of a unit.
Information in this section was contributed by Craig Schroth.

Hint: Selling vehicles:
Place a vehicle in the repair bay to sell it.
Information in this section was contributed by Jason James.

Hint: Selling troops:
Place troops next to or inside the items that are being sold. For example, when playing as the GDI, build a transport and repair pad and place five soldiers in the transport. Place the transport on the pad and sell it to get full price for the item and the men.

Hint: Killing multiple grenadiers/flamethrowers:
When attacked by a group of flamethrowers or grenadiers, just kill a few of them to set off a chain reaction that will kill the rest.
Information in this section was contributed by Pika312.

Hint: Gold NOD weapons:
Play as the GDI and capture a NOD airstrip. The GDI forces there will continue to build NOD weapons with a gold tint.

Hint: Finding money:
Destroy the churches in the villages to find $1000.
Information in this section was contributed by Matt A.

Hint: Scouting:
If you are trying to scout land the best way is to use Stealth Tanks playing as the NOD or Suicidal Humvees as the GDI.
Information in this section was contributed by Koehler.

Hint: Minigunners for less money:
If you need money and you want to make minigunners, do not train them. Make a Tiberium Silo and sell it . You will get three minigunners and a small amount of money. For the same construction time and three times less money you will get the same result: three minigunners. This strategy will work with any structure other than walls, but the Tiberium Silo is the cheapest building.
Information in this section was contributed by Chacal15.

Hint: Build NOD attack chopper:
To build an attack chopper for the Brotherhood of NOD, simply take over their main base and the option for an attack chopper will become available.
Information in this section was contributed by Matt A.

Hint: APC bomb:
Steal or make an APC, and fill it with flamethrower men. Send it to the enemy base and place it next to a building. When it is destroyed, the flamethrower men will explode. Two such APC bombs can be used to destry a Construction Yard.
Information in this section was contributed by Adam Rutherford.

Hint: Faster Ion Cannon and Nuclear Weapon charge:
Build more power plants to get a faster Ion Cannon and Nuclear weapon charge.

Hint: Taking out Lasers:
The fastest and easiest way to take out Lasers is to use three Flame Tanks -- you will barely get damaged.
Information in this section was contributed by Matt A.

Hint: Taking out Guard Towers and Advanced Guard Towers:
Build Artillery and send them to attack those structures. They shoot from such a long distance that the Towers can not shoot back.
Information in this section was contributed by Matt A.

Hint: Tiberium Factories:
When you destroy all your opponent's Tiberium Factories, you can shoot one of their structures a few times for them will sell to it. However, make sure you take out their main base first or they will not be able to rebuild the Tiberium Factories.
Information in this section was contributed by Matt A.

Hint: Keep tanks from getting destroyed:
Get some men and put them in the front of your tank. When the enemy opens fire, they will shoot at the men instead of the tank.
Information in this section was contributed by Gameshark255.

Build a repair bay fairly close to the entrance to your base and place a tank on it. When ever an enemy fires at it, the tank's health will be restored.
Information in this section was contributed by Mnracerr.

Hint: Enemy shoot each other:
Take a quick unit and speed it through two enemy units to get them to shoot each other.
Information in this section was contributed by Setzer123.

Hint: Distracting the enemy:
You can use units such as mini-gunners to distract the enemy and overwhelm them. They will not attack until the gunner dies.
Information in this section was contributed by Setzer123.

Hint: Selling out before enemy attack:
When the enemy is attacking your buildings, quickly sell them before they be destroyed. You will get money back, plus three mini-gunners and a technician with a shotgun.
Information in this section was contributed by Mark Couch.

Hint: Using walls:
Enemies will not attack walls. To use this to your advantage, build them to block enemies from getting to Tiberium Fields and your base.
Information in this section was contributed by Setzer123.

Hint: Destroying tanks:
Do not waste a lot of men on an enemy tank. Use two rocket launcher men. A tank will not crush them and cannot kill both of them before they destroy the tank.
Information in this section was contributed by Adam Rutherford.

Hint: Winning as NOD:
Build a remote construction site. Then, build a laser turret but do not place it. Send the construction yard truck close to your opponent's base, then make it into the yard. Quickly get the laser turret and place it next to the yard. Note: Make sure you have enough power before you start building.
Information in this section was contributed by Adam Rutherford.

When playing as NOD in missions where GDI has the Ion Cannon, for example Nod Spec Ops 2, build a SAM site. While the SAM site is up, GDI will not strike any buildings (Turrets, Airstrips, Construction Yards, Etc.), except the SAM site. However, if you build an Obelisk Light, they will hit it. The GDI favors hitting in this order: Obelisk, ADV. Guard Towers (GDI), SAMs, Turrets, Tiberium Refineries, then Airstrips. They then attack the other buildings at what appears to be a random manner.
Information in this section was contributed by Matt M.

Hint: Winning as GDI:
In missions that you have the Ion Cannon but NOD does not have its nukes, build as many Guard Towers and Advanced Guard Towers as possible in the path that Nod attacks. Then, use the Ion Cannon and air strikes to destroy the NOD Refinery, Silos, Construction Yard, Airstrip, Hand of Nod, etc. If you have to destroy SAM Sites to get your Air Strikes, send Orcas one by one and destroy them with a Ion Cannon. Hit while it is above ground.
Information in this section was contributed by Cory Armstrong.