HELP!: Identify this weapon

[Kommissar]

hey everyone, i've become really captivated by this version of the Joker and harley, and i would love to build the entire costumes of both, for my wife and i.
For the most part i've identified what things are, or feel i can build the likeness but the shoulder rocket launcher escapes me,
what is Joker firing at the Flash and Bats?
best shot of it is around 1.40, and again at 3.16
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what is it? or what would you use a good existing base to build from?
obviously non-firing and con-safe.

 

[Cenobyte]

I wish I knew, but it sort of looks like an upside down terminator rifle.

 

[Pete Cooper]

Not in current existence, that's for sure. But it bears a shocking resemblence to the rocket launchers used in plenty of anime (most notable being Gundam from the top of my head - especially with the top-loading magazine at the rear)

 

[Kommissar]

hmmm.. are there any airsoft guns with the shoulder mount like that in existence perhaps? i could always build it from that area.

 

[jimmydellamorte]

Appears to be a custom design:

 

[breen2057]

ive been playing airsoft for a few years now but ive never seen any gun like this in play or on any of the websites. looks to be a custom job.