The sooo strong army!

[Adagio]

Why is it that people should be so scared of the army? In all my games, the armies has been very week. I see often an army of cavalery, going to battle against a single veteran cavalery, but still the army ends in the red before it wins the battle...if it wins...

This makes the army pretty useless, since you're using 3-4 units to form an army, but still the army is just as strong as a veteran unit!?!

Or is it just my computer which screws up the army?

[Robert]

You can use an army to break one strong defending unit.
I always attack cities with two armies first, after that the 'normal' untis finish it.

that makes you lose less units, since armies most of the time win (but end up in the red indeed)
Make sure you have cities with barracks near.

[Moonsinger]

When attacking a city of size 13 or greater defending by infantries, I always bombard the city to reduce all defenders HP to 1 before I send in my 18 or 20 HP armies. Work every time!