Nod has a killer late game army, but why risk allowing your opponent a chance to comeback when you can hit them with some base owning powers and some support powers that can really increase the effectiveness of your current fighting force.
Decoy Army
A great situational power that can really help you bluff your opponent; this tends to be forgotten in the later stages of the game, though. Usually the main use for it is to decoy Scorpions but Cloaked Flame Tanks or even Stealth Tanks can be effectively decoyed. It's probably better, though, to use it before your units enter his sight: he will be fooled into thinking that he is facing a larger army, and also will waste time and shots firing at decoys. Use this with another distraction for the best results.
Radar Jamming Missile
A very useful power that doesn't see much action. Use it before unveiling some Stealth Tanks in the rear of an enemy base or dropping a Tiberium Vapor Bomb on an unexpected target, or for no reason at all. I recommend spamming it; constant disabling of his radar will both make him look for an attack that's not coming; buying you time to position forces well, and eventually dull his reactions, meaning you can have a greater chance of dealing a crippling blow whilst his attention is distracted. Note that it can be used as a partial counter to GDI's Radar Scan.
Cloaking Field
Used most often to cloak Flame Tanks or kill infantry, but it doesn't need to stop there. If you're in the business of upgrading Avatars, use this to cloak some Flame Avatars to send to the back of your opponent's base. Because of the high cost, it is advisable to use it to kill infantry only when you have $5000 or more. Also, do not use it against Zone Troopers - the power won't do enough damage to kill them. Instead, use Venoms.
Check out the
1.05 Kered13 vs. -Netput replay to see good cloaked flame tank usage.
Shadow Strike Team
Outside of the Shadow Rush, this sees little action. However, Tech Center Harrassment in the late game is by now a very viable, and almost essential strategy, and this is one way of accomplishing that aim. It's usually advisable to drop the Shadows near your base or the enemy base, and let them run the rest of the way. Also, as with all stealth units, micro them properly to make sure they avoid any anti-infantry units as much as possible. If they survive, you could leave them in the enemy base as scouts, periodically making strikes at the enemy's power or other important buildings...
Mine Drop
Unlocked by construction of an Air Tower, this is irritating at the best of times and a royal pain in the backside at the worst of times. However, good use of this can actually present you with a win if locked in a base-rape situation. For this reason, be sure to get an Air Tower as soon as it's opportune to do so; sometime in the middle or early late game stages. Drop them in front of a War Factory, or better yet, in the middle of a Tiberium field. Alternatively, drop them in enemy tank groups, but be sure to micro correctly and drop them where the tanks will actually pass through, if at all possible.
Don't bother dropping the mines as a counter to Dozer Blade-upgraded Scorpion Tanks, though, or if your enemy has stealth detection nearby.
With the Catalyst Missile and Vapor Bomb being as powerful as they are, the Tiberium Chemical Plant becomes EXTREMELY important in the late game. Protect it well - it is likely to be a very high-value target, and will be costly to replace.
Seed Tiberium
Too cheap to be true, this ought to be spammed as much as possible, especially when facing GDI - the economic advantage is well worth building the Tiberium Chemical Plant for. Put it this way. If you face GDI on Tounament Arena, and the game gets into the late stages, you can use GDI's expensive unit costs against them, and destroy his Spikes to starve his economy while you spam whatever you wish.
Use it as soon as your TibChem plant is up. Try to target the drop in an isolated area of a Tiberium field, to make sure as much Tiberium as possible is dropped. Also avoid dropping the Tiberium into a Blue field; it will take up space that could be used to grow Blue Tiberium instead. As with all powers reliant on the Armageddon Bomber, don't use it if there's the risk of the plane being shot down.
Catalyst Missile
The bane of any non-Nod player... It is very powerful on it's own; a well placed shot can knock out 3 or even 4 Refineries, but it really needs support in order to be most effective. Most especially, have some units on hand to finish off Harvesters damaged by the blast - Stealth Tanks or Vertigoes fit this role nicely. It also works pretty well as an infantry killer in more desperate situations. Just be aware that the sound given off as the missile launches can be heard by all players; a faster opponent may sell off the Refineries before the missile hits. An interesting, if not expensive alternative would be to use the Seed Tiberium combo presented in the Kane Edition DVD for a little more damage, but as previously mentioned, you'll need to make sure that there is no AA that can kill off the Armageddon Bomber en route.
Tiberium Vapor Bomb
The mini-nuke. It can be extremely deadly, and can be a good way of taking out an unguarded Tech Center, Crane, War Factories, or masses of pesky infantry or groups. Using it in tandem with Vertigoes, Scorpion Tanks, or even Avatars can reap real results as well. To repeat previously given advice, make sure that the path to the target is relatively free of AA - the Armageddon Bomber won't stand much of a chance against moderate AA fire. In the same vein, if you're in the mood for killing massed Missile Squads via a support power, then don't use this - take the Catalyst Missile or Cloaking Field instead.
Nuclear Missile
What would Nod be without its Nuclear Missile?
As a superweapon, it faces many of the same flaws as the Ion Cannon and Rift Generator - the 7 minute timer and visibility to all players on the map, meaning it needs a lot in the way of defense. However, it can easily make sure you win a game, as you can force your opponent to make poor assaults, or simply blow his units to oblivion. Use Disruption Towers and some Stealth Tanks nearby as a partial counter to the ever-present threat of Stratosphere Fighters, and only build it when you want to pressure your opponent when you have a clear advantage, or when you are caught in a stalemate position. To see how important a nuke can be, check out the
W0NnaPl4y vs. Khufu replay.