[Background & story]

Why are the aliens attacking earth?
...falls ancient flying object, aliens need ancient technology, humanity has refused to return the aircraft, so there was a conflict.

[Disposable rocket launcher]

I want to share my idea; Propose to add in the X2 disposable rocket launcher M72 LAW

Weight: 2 kg
Time Units (TU) per shot:        
-Snap=16
-Normal=20

Pros:
-low TU cost
-low weight

Compared to rocket launcher

Weight: 6 kg
Time Units (TU) per shot:
-Snap=27                            
-Normal=36                           

Pros:
-multiple types of ammunition

Cons:
-big TU cost
-big weight