Introduction: Two K'nex Halo Covenant Guns.
I made a mod of this gun, making it a little bigger (first pic). Mostly theirs, but 'expanded' a bit.
And I made a Needler to go with it (second pic).
The plasma pistol and needler you can probably both build from the pictures, unless you don't have enough k'nex. ;)
Add a Teacher Note to share how you incorporated it into your lesson.