Attack will help you when attacking other vikings. Defense will help you when other vikings attack you. While it seems basic, attack and defense are helpful when compared to another viking's, so there's a large variety of builds. A few examples: -Large attack, low defense, medium health: Can win most attacks, but seeing other clans (with similar chieftain number) lose is quite a rare sight. Good at hiding in hospital. -Large attack, large defense, very low health: Hated by most, its a great fighter but, you'll do pretty badly against bosses and will get very low XP fighting. -Medium attack, medium defense, medium health: An overall Viking that will win some fights both ways and will do bosses good enough.
Well it's all proportionally-speaking. Just invest as much as you feel you need considering: -Damage done on battles. If it's too low, that means health needs improvement. -Bosses. If it takes simply too much stamina to get to the minimum, and they're not very tough bosses, then you're possibly lacking some.
