[2020] I'm not great making stuff from cardboard but here is my attempt at H3: ODST magnum so far.

This looks great!

If you ever want to check in on some of the details, we actually just released an official cosplay guide! It has some close-up shots of the pistol starting at page 63: https://www.halowaypoint.com/en-us/news/cosplay-guide-the-rookie