Chariots are there to disrupt not to fight. Use them and their javelins to whittle down the opponents infantry but be careful of enemy skirmishers, archers or slingers as they will tear your chariots apart. Chariots are generally good against cavalry. Against light infantry they'll die quickly so don't even approach them. Their uses against heavy infantry are generally to push through the formation, disrupting it and making holes, which you can then fill with lighter troops. Once a unit of heavy infantry is out of formation it loses a lot of its strength.

Generally, melee with chariots is a mistake.

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