Shotgun with Rifle Rounds?
Sniper with Shotgun Shells?
MachineGun that Launches Grenades?
Silenced Grenade Launcher?
Yes.
Saw a lot of little translation errors all around, you may want help with that if you are gonna fully develop this game, which you should because this is a good concept.
Here is one weapon I got - Silenced Anti-Material Rifle that shoot Grenades that explode at cursor with AirBurst Control, with accelerated projectile flying speed! Replace barrel with Looong Barrel and you'll get a grenade launcher that can shoot behind corners and over cover!