In Grepolis, you may build units in order to attack other cities or defend your own. Land units can be used to pillage other cities on your own island, whilst naval units can be used to transport land units to other islands or can be used to attack others' naval ships. Each land unit has one of three weapon types, as well as three defensive figures which show how well it can defend against each weapon.
You may build land units through the Barracks (with the exception of the Militia). Naval units can be built through the Harbor.
Unit speed values are based on Unit Speed 1 worlds. For higher speeds, multiply the values as needed.