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There is no universal "best" army setup for TATW. It always depends on your playing
style, your skills and mostly on the enemy you face. For every unit there is at least
one useful counter-unit that maybe sucks on fighting other units but is very effective
against certain enemy units.
Pelagir Marines f.e. are really great against cavalry, Mumakil and Trolls but they don't
bring you any good advantage when you face an enemy stack consisting of mostly archers.
I guess you get what i mean.
But the problem (and i like that) in TATW is that you can't always set up your stacks for
a specific enemy because you have very long ways to travel to the enemies due to AORs,
lacking money and culture levels. But you should at least fit your stacks to the enemy
faction you are planning on fighting. (always try use the enemies weaknesses and disadvantages
to your advantage.)
Additionally you should rely on the unit-advantages of the faction you are playing. That means
for elves go with archers, for Rohan cavalry, for orcs on massive cheap units and so on ...
For a universal stack:
First of all - take a spy with you (he can join the stack that you use). Use this spy on enemy
stacks that you gonna attack, that you can prepare the upcoming battle.
To at least balance battle results you have to create two stacks that you assemble before you
attack by fitting the one you will use on a specific enemy army. This two stacks should have
units of every type: melee, archers, javelins, cavalry and very important in a 50 turns+ game
ballistas/catapults. Also it is important to have cheap militia in your stacks that are abdicable
which should always build the first line in your battle formation - because that units you will loose
for sure. With the information the spy gathered you can put together a army out of your two stacks
that fit the enemy army.
But the most important thing is to get an own fighting style. Create own tactics and fighting strategies
and an own fighting style. With the right strategy you can beat the game with simple elven militia
that is available from the start.
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