If you plan on being good at Warcraft 2, you need a good strategy. I have listed all the strategies that i have found to be useful from personal experience. Be cautious though, as some strategies will not work so well when used against human enemies. I have also included unit info(what's what and what it's good for).
Basic Stategies
When you begin a game, survey the area right away. Find out the positions of anything important nearby, such as enemy towns, gold mines, water, etc. Then build as fast as possible!!!! Depending on your location and surroundings, the best oreder to build in is Town Hall(duh), farms, Barracks(if an enemy is close by), Lumber Mill, Blacksmith, then upgrade to a Keep or Stronghold. All the while you should be pumping out the peons for resource gathering. In early stages places peons about 50/50 for Mining/Forestry. Later on you can cut than down to about 60/40 or even 70/30. Also upgrade unit properties fast too, as a level 5 footman/grunt will be much more useful than a level 1 footman/grunt. Here is how to handle some situations:
Open plains, nearby enemies, high resources
When playing these types of levels I find that the computer is relentless with grunt/footman attacks and will quickly ally with other computers to basically kick your butt.
All I can say is to build a barracks as quickly as possibly and never stop producing footmen and archers(usually on a 2:1 or 3:1 ratio), and cannon towers can be useful in this situation.
And dont bother trying to run him out of resources.
Surrounded by trees, high resources
Different from being in an open area, you can save the production of a barracks for a while. The easiest way to beat these is with dragons/gryphons. Quickly upgrade to a castle and build two or maybe even three Aviaries. Note you should build guard towers and archers to prevent yourself from being annihilated by fliers. Although this will usually cause the computers to counter with 2 or 3 Aviaries of its own, its better than nothing. Quickly attack and take out the towers(only if they are guard towers, cannon towers can't touch fliers) and any other units that can damage fliers. After that, their town will be utterly defenseless as you destroy everything left.
Surrounded by trees, low resources
This one is a tuffy. Dragons and Gryphons will be too expensive to produce, so quickly cut through the trees to find more gold. Keep your defenses beefed though to prevent ground attacks.
Open area, separated from opponent by water
If this is the case, you don't need to build quite as fast, but it would'nt hurt. Keep some defense around in case of transports bringing over enemies, but a few ballistas and cannon towers at the water's edge should slow down that threat. Build a Seaport and build a small fleet of battleships or juggernauts. Take out the enemies seafront with these, then take in some troops and fliers to finish them off.
Computers
I have to admit, the AI can be very poor at some times. They fight to the most often, and can fall into traps very easily. A couple useful strategies are as follows: 1. When being attacked by fliers, take a peasant or archer and run around beneath them. They will shoot at you, and injure themselves in the process. 2. Build cannon towers around all gold mines. When their current one runs out, they will sometimes go all the way across the map to mine gold, rarely building a Town hall or bringing defense. The towers will pick them off, and they will continue to make more peasants to mine more gold. This will run them out of gold after a while. 3. After you build good defenses, the computer will stop attacking you and go into a resource-gathering mode, and won't build new troops. 4. Instead of walls, build farms to block ential susceptible spots. Leave some room behind these then build cannon towers. When they attack, they will attack the farms. Put some peons there to repair it and its almost invincible, while the towers take out the enemy(keep some fliers handy in case they bring in some catapults). 5. Build in clumps to conserve space, as computers rarely build demo squads.
Humans Vs. Orcs
In this ongoing debate, there are outstanding debates on both sides. Personally I like humans better, but orcs are just as good sometimes. First of all, human mages are way better than nights, simply because their spells are better. Invisibility is an invaluable addition, as walking into a town with a mage your opponent can't see and blizzarding the place is very damaging. And fliers no more with polymorph(only problem is it takes so much mana). Paladins are very useful with all three great spells. Holy vision will cut all scouting costs, while healing will keep your troops healthy for another attack. Exorcism is also a great adiition when facing orc opponents as it s the knights and their armies of skeletons, but don't waste your gold on it if there is no orc players. In fact, the whole game would be in favor to the humans if it were'nt for the most devastating spell held by the ogre-mages. Yep, you guessed it, Bloodlust. Bloodlust triples the damage of a unit, and a cube(9) of bloodlusted ogres can usually take out armies twice their size. There is no really effective counter to this spell, but slow will prolong the lives of your defenders. In the case of axe-throwers and rangers, I like the ability to do 8-14 damage per shot with rangers rather than regenerate at the slowest rate with axe-throwers.
Advanced Tactics
Magebombing
Magebombing is extremely useful in many situations. The best time to use it is when you have located a large enemy outpost. Take one mage at full mana, and place him just outside the attackers sight. Cast blizzard once on them and they will immediately charge your mage(Use the hotkeys, this can be tricky). Cast it again as many times as you can get off on your own mage the attackers will disregard the blizzard and attack your mage. Although your mage will get wasted, the enemies troops will probably be much more damaged.
Taking out towers
Unguarded towers are the easiest defenders to take out. All you have to do is carefully place a catapult(whose range is greater than both guard and cannon towers) and shoot away.
Unit Descriptions
Humans
Note: I am only going to show humans because 90 percent of units and building are the same, but i will note differences if any in description(in order top left to bottom right, humans/orcs).
Gnomish Flying Machine/Goblin Zepplin
Use these for scouting and spotting submarines, as they are cheaper, quicker and less of a threat tha dragons. Cost:500 gold, 100 lumber
Gryphon/Dragon
In early stages these can be devastating because of their strength and flying ability, but are expensive and slow, and are very stupid(clusters of them will often damage each other). Cost: 2500 gold
Peasant/Peon
Basic land units. Make lots of these and gather as much resources as possible. Cost:400 gold
Footman/Grunt
Basic land attack units. These are useful in numbers early on as defense and offense, but produce knights and ogres instead as soon as possible.Cost:600 gold
Archer/Axe-thrower
Because of their range, ability to attck fliers, and good upgrades, these are very useful attackers as well as defenders.Cost:500 gold, 50 lumber
Knight/Ogre
The stronger alternative to footmen and grunts, these can be upgraded to magic users and also have a higher toughness.Cost:800 gold, 100 lumber
Ballista/Catapult
They are slow and useless in close range combat, but used in rear when fighting and as sea defense, they can be very useful due to their sheer strength(especially when upgraded). Cost:900 gold, 300 lumber
Dwarven Demolition Squads/Goblin Sappers
These can be very devastating when buildings are in clusters, and can attack too.(Note: Invisibility won't work on these units,they will just blow up.)Cost:700 gold, 250 lumber
Mage/Death Knight
Powerful magic users, they can do large amounts of damage with blizzard/death and decay, but are weak and better used in rear lines and one at a time.Cost: 1200 gold
Farms
Build an excess amount of these so you never run out of food for your units. Destroying your opponents farms will stop him from producing units.Cost:500 gold, 250 lumber
Town Hall/Great Hall
Most important building in the game. Build it close to a gold mine for better efficiency. Cost:1200 gold, 800 lumber
Keep/Stronghold
Building a barracks enables you to upgrade to this, and a keep lets you build Stable/Ogre Mounds and an Inventor or Alchemist.Cost:2000 gold, 1000 lumber, 200 oil
Castle/Fortress
Build a Stable/Ogre Mound to upgrade to this. At 2500 gold, 1200 lumber, and 500 oil, it is very costful, but very useful. This lets you build gryphons, mages, paladins, etc.
Barracks
Another important building, this one lets you train your troops.Cost:700 gold, 450 lumber
Lumber Mill
This building increases lumber production by 25, lets you upgrade you archers/axe-throwers, and your peons can drop their wood off here.Cost:600 gold, 450 lumber
Blacksmith
This is for upgrade purposes on your weapons, shields, ballistas, and also allows the production of knights/ogres.Cost:800 gold, 450 lumber
Stables/Ogre-Mound
These in hand with a Blacksmith will let you create Knights/Ogres, which are very useful throughout the game.Cost:1000 gold, 300 lumber
Church/Altar of Storms
Upgrades your knights to paladins and ogres to ogres-mages as well as researches spells for them.Cost:900 gold, 500 lumber
Gnomish Inventor/Goblin Alchemist
Enables production of Scout fliers and demo squads.Cost:1000 gold, 400 lumber
Gryphon Aviary/Dragon Roost
Produces Dragons and Gryphons, but at a hefty price.Cost:1000 gold, 400 lumber
Scout Tower/Guard Tower/Cannon Tower
Scout towers don't do any damage and are only useful for seeing submarines at bay/Guard Towers shoot arrows at a fairly fast speed, and can shoot fliers/Cannon Towers cannot shoot fliers and are useless at close range, but are good sea defense and land defense(behind walls)Cost:550 gold, 250 lumber/+500 gold, 150 lumber/+1000 gold, 300 lumber.
Mage Tower/Temple of the Damned
Produce Mages and -Knights and their spells.
Seaport
Builds all of your seagoing units, and enables building of foundry and oil refineries.
Foundry
Upgrades your ship's cannons, armor, and allows production of Battleships, submarines, and transports.
Oil Refinery
Boosts oil production by 25.
Oil Tankers
These can build oil platforms and haul oil, but thats about it.
Transport
For carrying troops across water
Battleship
Slow but very powerful. These can usually take out a Destroyer in one shot, and can devastate a town's coastline.
Gnomish Submarine/Giant Turtle
Moderately powerful and quick, these are useful for one reason, they can't be seen by opponents unless they have a tower or flier nearby.
Elven Destroyer/Troll Destroyer
Basic sea attack units, these do a fair bit of damage and are quick.
