*A colossus is considerably harder to create than guard tower.
*Can't be built ontop/inside/on a floor of a house, can`t attach parts to it inside a house. ''You cannot create that inside a building''
*Can not be turned or movedby its owner.
*Colossus placement is on tile you're on. Colossus will face toward you. Dropping unfinished will give you idea where it'll face. e.g. Facing north, upon completion colossus will face south.