This is a custom nerf gun, build around the Lepus pusher system, so it has a high cap rate of fire of 3000 rpm, about 50 a second. This is designed to fit on an ender 3, however, you might need to use Prusa slicer to slice it, because I think Cura won't let it fit. It takes talon mags.
You will also need a small handful of M3 screws, I suggest this: https://de.aliexpress.com/item/1005002109863123.html?af=761515&dp=6378_1634306536_13e50bf5f0d5174a7d2b2ee6304e367f&cn=6378&Afref=https%3A%2F%2Fwww.youtube.com%2Fchannel%2FUCDl4E7cxBudqBTkbW&aff_fcid=9237231e69e44e72bbfa0fca2287afd7-1634306536262-04015-7M7IEmQnY&aff_fsk=7M7IEmQnY&aff_platform=link-c-tool&sk=7M7IEmQnY&aff_trace_key=9237231e69e44e72bbfa0fca2287afd7-1634306536262-04015-7M7IEmQnY&terminal_id=577f5a045d594ba5a5ec5d63b3da6e27
And you will also need a 3s battery, I suggest this: https://www.amazon.com/TATTU-450mAh-Battery-Torrent-Flite/dp/B0714GN73V/ref=sr_1_2?dchild=1&keywords=3s+450+lipo+tattu&qid=1634306623&sr=8-2
However if you use that battery you're going to have to get a connector for it and I'm not sure what that one's called lol
If you build this PLEASE let me know in the comments, tell me how it worked for you