Not the best work ever, but not bad either. The spear head is a foam core with worbla over it. It didn't bond to the foam like I'd expected, so it's not as good a shape as I'd hoped for. The black/gold portion is foam board (like you'd use for projects) with worbla on top. That came out better.
The circle portion is styrofoam from Michael's/Hobby Lobby that I cored and shaped. The stripes are string. The triangle on top is foam board with duck tape.
It's big. It will be interesting getting it into the car for Momocon and may even have to ride on top. But, daughter is happy she now has the spear to go with her character. (Don't ask me who it is, I have no idea.)