Army
The Karnnish army is primarily reserve forces. The army patrols outside the walls of the city and is relatively small as this is a time of peace.
Those who wish to join the city guard must patrol with the army first.
The rank system is undefined (metagame) but this is one
City Guard
The city guard is much larger than the army due to the need for active duty members.
The city guards deals primarily with activities within the city.
Duties include, patrolling the streets, border/wall patrol, detectives, and a "SWAT"-like team (magic?).
There are very few mage guards, but those that exist are strong.
There are two special teams of councilor guards. The internal and external threat teams (of about 5 or 6 members each)
The external threats team has a mix of city guard and army responsibilities.