Defense Guide :

1. Mines. Remember, max 30 mines limit. 6 mines is what is counted for as being able to take out an enemy. All "critical" buildings (often the Obelisk and PowerPlant) should have 6 mines at each entrance. The rest will have to share the mines, 3 mines at each entrance or more if possible.
Remember, every map has their own CRITICAL buildings!

2. Critical Buildings : They are counted as critical if they are easy accessed due to base weakpoints or are important in other matter due to the maps structure.
An example of this is the PP on Hourglass on GDI side. Many don't think how easy it is for an APC to get behind the WeaponsFactory without heavy damage, and from there have easy access to WF, TiberiumRefinery and PP. Often the PP is tried taken out due to the importance of defense on the map. I suggest 6 mines at every entrance on PP and Advanced Guard Tower.

3. As defense vehicle, you should as NOD always either have a Light-Tank or the Stealth-Tank. That's due to 2 reasons : They are quick and have high firepower.
As GDI you should always have the Medium-Tank of the same reason.

4. As defense character, you should as NOD always be Mendosa. If not, something else with either high firepower of quick firerate.
As GDI, Mobius.
WATCH OUT FOR SNIPERS!

5. In case there is a beacon planted in your base, make sure you get rid of the ones defending the beacon before attempting to disarm it!

6. If there are vehicles pounding on a building and you have no way of repairing it in time for someone to assist you, try to get as much cash as possible (if it seems safe) and buy Mobius / Mendoza and get rid of the vehicles!

7. If there are C4 on the MCT, get rid of the C4 first (if there is time) instead of just repairing the MCT (of course, you need to consider what is best in each case)

8. In case of flying vehicles attack, be a sniper! They are very effective against thoose flying annoyments. Snipers are also excellent against MRLS and Artillery and other light vehicles.

Attack Guide :

1. All attacks have different tactics!!

2. APC : Use APC with either minimum 2 Engineers or 1 tech / hotwire (again, this is MINIMUM), rush into the entrance of a critical building, and place the C4 ON the MCT.
IMPORTANT! Place the timed C4 first...if you have come unnoticed into base, wait to blow the remote C4 until the timed has blown off!
Then the enemy won't be warned. 1 Engineer is NOT able to take out a structure.

3. MRLS : Make sure you are an engineer / Technician / Hotwire, the MRLS has powerfull weapon, but can't take much damage.

4. Actually, I like to suggest being a Engineer or higher class at all times when driving a vehicle...then you are able to repair it quickly yourself and even have C4 in case the base defenses are gone.

5. Sniping. Try to find dark or hidden areas of a map with good overview of the other's base and open fields. I suggest not to kill off people with characters that costs nothing, don't want to warn them! Wait until you see an upgraded character. Unless they are rushing for your base of course.

6. Stealth. They are excellent to use for planting beacons, due to their heavy weaponry and their stealth!

7. Whenever you are shooting at a building, try to hit the MCT even from the outside. The structure will take more damage even with an outside MCT hit. The optimal will of course to have the door OPENED on the structure so you get straight access to the MCT, but that would need you to have a partner with you and pure luck. Happens rarely, but it DOES happen.
In addition, it's nice to have an extra partner for "softer" targets. 2 in 1...

8. Flamers. Use at LEAST 3 flamers when going straight for an AGT.

9. Mammoths I am not sure on though I would like to believe a 3 Mammoth rush would secure the takeout of an Obelisk...it's pretty hard repairing in time with that amount of firepower pounding in!

10. Always try to get to as close to the base unoticed as possible. If you see someone guarding or scouting, reconsider going another way instead of rushing in the base.
If they allready DID detect you, go quick before they have time to gather a defense!

11. Try to take out the Critical buildings first!! (often the PowerPlant or the Defenses)

12. If you have blown all your C4 and can't really do much more use at the position you are, get killed! That's a way for the enemy to give you an "express ticket" home. However, often good and professional players ain't dumb enough to do that, but shooting at them with your gun will often cause them to be annoyed enough to take you out.
Or walk into Tiberium or get run over by enemy Harvester.

13. COOPERATE!!!!!