With update 42848, Chieftains costs 700 food, 500 gold.With patch 5.7, Chieftains gives infantry +4 attack bonus against camels.With patch 4.8, Chieftains now affects all infantry units and gives them additional +2 attack bonus against camels.Chieftains gives Berserks +5 attack bonus against cavalry.Chieftains gives Berserks +4 attack bonus against cavalry.Portuguese: Researching Chieftains is 25% faster.Also, the effectiveness of Pikemen is increased, as the damage gap is now only 5 anti-cavalry damage, making it more forgiving that the Vikings lack the Halberdier. Archers, however, remain a heavy threat to them. In fact, the Viking Champion can trade cost-efficiently against Paladins, something no other Champion can do (except arguably the Malay Two-Handed Swordsman, depending on how much gold is weighted). With Chieftains researched, they become even more versatile, as they can now counter even heavy cavalry units quite effectively.

Apart from the Teutonic Knight, the Berserk is one of the most durable infantry units in the game, and the Viking Champion is not far behind.