Don't be like the other raiders, who just slap some fur on their shoulders and call themselves a bear. No, no, no. You be a true warrior of the North. Choose a costume that's as fierce as a bear, but with better hair.
Those fancy runes on your shield? Yeah, you can just use a Sharpie to draw those on. But if you really want to go pro, invest in some fancy calligraphy classes or a good ol' fashioned Viking font set.
A good Viking's got a good sword, a good axe, and a good beard. Don't be that guy who shows up with a Nerf gun and a fanny pack. You'll be laughed out of the village.
It's not just about the costume, folks. It's about the attitude. Practice your battle cry in front of the mirror, in the shower, in the car. You never know when the raiders are coming, and you want to be ready.
May the best Viking win.