The Natarian Guardsman is a fierce fighter. The guardsman has attributes comparable to, and sometimes sometimes surpassing, cavalry. They are all well-rounded fighters and have above average stats for infantry. These factors allow a guardsman to excel in defensive as well as offensive situations. Guardsmen, like mostly all Natarian Army units, are controlled by NPCs, and players can not train or fight with them. For travian advice go here
"Adored by their people and feared by their enemies, a Guardsman fights without a mount but is nevertheless one of the most valuable soldiers in the Natarian army, thanks to his versatility. They are deemed as well trained fighters, leaving their enemies with almost no chances to win. Due to their heavy armour, they can be used as strong and reliable defense troops too."
-Travian FAQ