For Halloween this year our youngest decided (on his sister's clever suggestion) to be a medieval knight or king. He could carry a sword, belt up a long shirt as a tunic... He liked the idea.
The night before Halloween I got inspired and made a really tall yellow crown, and a long shield of foamcore. I thought he'd like a dragon rampant, and I asked him what color he wanted it. "Red with blue eyes," he replied.
Here's the costume that resulted (we don't show our children's faces on our blogs). The sword was made long ago out of foam tubing cut lengthwise.