Infinite Firestorm Wall
If you have a firestorm wall and it is fully charged, you can make it last forever without having to turn it off to charge. First charge your wall fully, then turn it on. Before it turns off or runs out of power sell or turn off your power plants until the words "On Hold" appear in the firestorm Icon. Your wall will stay on forever and will not run out of power until you build or turn on your power plants.

Level 9 Hint
At this moment the most asked question is: "How do I get behind the laser cannon ( The Obelisk of light )"? Well, at the right of the cannon there is a small base with a 'hand of NOD' building and a few power plants. First of all you must destroy the units on that base. After that, destroy all the power plants so that the NOD has low power. Then you can pass the laser cannon or you can destroy it. When you go to the top of the map there is a base you can capture. Capture it and destroy all NOD units.

Easy Way To Capture Construction Yard
To capture the enemy construction yard while you are the Nod, Build a subterranean APC and put some engineers into it. Then tell it to go to the enemies base and unload the engineers to capture the base.

NOTE: THIS WILL NOT WORK IF ENEMY HAS BASE PAVED OFF.

Infinite Troops
During the second mission build exactly 68 infantry to allow you infinite troops on the 12th mission (make sure the troops don't die or get injured or the cheat is invalid).

Hijacking Vehicles
Take a Mutant Hijacker into a city and find a car, truck or a bus, and select it. Now you have control over the Vehicle. They are used as transports.

Kill a Cyborg Commando in One Hit
If you want to kill a Cyborg Commando, without losing all of your units, there is a very simple way to do it. (You have to be able to build a GDI Firestorm Wall Generator, and Firestorm wall sections.) First fortify your base and build it up until you have the option to build a Firestorm wall, and sections, then build firestorm walls across any sections where an enemy can get into your base. When a Cyborg Commando is over one of the sections turn the Firestorm generator on and Blam! All of your problems are solved.

Baby Visceriods
To MAKE baby Visceriods, order an infantry unit into Tiberium until the soldier dies. Be careful though, once they become adults they are not friendly.

Secret Level - "Power Grid" (GDI)
In the level where you must destroy the chemical missile base first select to free the mutants. Then take the level where you have to destroy the supply base. Instead of destroying all the chemical tanks you can go north west to find a train. Take the mutants and the ghost stalker with you that you just received by reinforcement, and complete the new objective by getting the ghost stalker on the train. Then destroy the rest of the chemical tanks and get in the level called The "Power Grid".

Special GDI Ending
Leave the NOD's "Temple of NOD" until the very end and make sure your ion cannon destroys it. You will get the special ending.