Both of those assumptions are wrong. A person chooses up to 16 units with the amount of money available. One could choose to take all cavalry, or all infantry, or go heavy on missile units, or take a balanced army, comprising of all three types.
Then how it plays out depends on the individual in command. I prefer to do multiple feints and then pin with infantry and outflank with cavalry. Other people prefer to do full, head on attacks. Still others prefer to sit back and let themselves be attacked.
If you are on a team, you will have to work together to succeed. A team that is comprised of three good players that do not work too well as a team can and will be beaten by a team of three average players that work together.
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