Combat: Because units can win but be wounded in the process, always try to
have a tactically advantageous retreat position. That wounded Chariot may be
vulnerable to a clunky Legionnaire out there on the plains, but back him up
into some hills or mountains, and the counterattack is much less sure. This
technique also has the benefit of luring enemy units out of their protective
cities and into dangerous combat.
Technology paths: At the start, if there is no direct military pressure on
you, press for the Monarchy as soon as possible by researching Ceremonial
Burial and then Code of Laws. Monarchy now gives you three units per city
without upkeep, so this is the perfect long transition to the Republic,
especially if you are using the quantity approach. After you pin down the
Monarchy, go for Mysticism next--the Oracle will make your life much easier
during those awkward growing years.
Fortresses: Don't build them! No matter how tempting it is, sooner or later
they will turn into hiding places for the enemy. In fact, the computer loves
Fortresses so much it doesn't have enough units to cover half of them, an
enthusiasm you can take advantage of. Use them as healing shops for damaged
Villages: I have yet to see one village break out in barbarians when a city
has been built next to it. Don't feel like risking your Settler? Put down
roots and wait for one of your inexpensive Warriors to reveal a prize. Also,
look for plenty of villages along the polar land caps.
The big bribe: Get out of Despotism and into a crown before picking any
fights--the computer now has a real knack for bribing units and towns unhappy
with their Despotic Leader (and you know how much money the computer seems to
have to throw around). Once spies can pack nukes, you should leave one spy on
guard in each of your big cities, just in case.
The ol' take and give: If you are broke and a neighbor isn't, and you both are
relatively equal in technologies, taking over a city, even though you know you
will lose it right back, can empty his treasury into yours with just a couple
of repetitions. Just make sure you spend all those gold pieces before you
cough up the city again.