This is my first instructable so be nice. Anyway this gun features:
1. Removable mags, courtesy of Killer_Safe_Cracker
2. A lever mechanism for ease of cocking (I know it isn't true lever action as it doest chamber a shot like a bolt action).
3. A wide barrel that enables multible shots to be fired like a shotgun.
4. Easy to add parts on the inside due to pins that can be removed easily
Con's
1. low range
2.low ROF
3.mags can be hard to preload

Step 1: Outer Body

1+2: make this (part 1)
3. add blue rods
4. make this
5 thread on to part 1

Step 2: Innards

1. Make
2. make
3. attatch
4+5. make this
6. make these
7.put them together
8.slot it in
9. add it on
10. close-up
11. clip the other one on
12. make
13. add
14. put in a green rod
15. add the other part
16. make
17. add
18. make 2 of these...
19. and one of these
20+21 add in order (put the other small one on too after.)
22. make
23.add

Step 3: Trigger

I was lazy here but it should be easy
1-3 various views of the trigger
4. attatch
Note: the broken rod isn't necessary replace the two black hinge pieces with a normal hinge and apply tape

Step 4: Lever and Pin

1. the pin (the string is 1 length approx 60cm long + tying space.)
2-4. the lever
5. don't forget the grey connector
6. insert pin
7. clip on lever
8. add the other shell

Step 5: Stock

1+2. build. The 4 blue spacers can be replaced with 2 small wheels
3. attatch
4. loop the strings over the wheels
5. build and set aside
6. build
7. remember the correct spacer placing
8+9. put them together
10.add it to the body
11. another view
12. make these supports
13. attach them

Step 6: Outer Panels, Sights, and Bands

1+2. make this big panel
3. attatch it
4. put bands on the trigger
5. put bands on the pin
6. make these sights
7+8. put them on

Step 7: Mag

I was lazy again. It uses the mag from the TBAR just without the stuff on top
link: https://www.instructables.com/id/TBAR-Thunder-Bolt-Assault-Rifle-1/step12/Mag/