Knights are built from a Stable that is Level 6 or higher. They are mounted units and are one of the fastest units in the game.
Knights are very good at knocking down buildings. They are much faster than Catapults which is why they are normally used. They allow for fast attacks, stopping the enemy from having time to prepare like they do if you send catapults. They provide an overall speed boost to any troop that does not contain extremely slow units like Catapults or Helepolis'
|Training Ground||Fighter · Bowman|
|Barracks||Swordsman · Archer · Hoplite · Gladiator|
|Stable||Cavalry · Knight|
|Workshop||Helepolis · Catapult|
|Trading Post||Ox Wagon|
All unit stats by level can be viewed at the Official Help Database