I have seen you before : Origin story

Snart's gun doesn't seem that different to handle than any regular gun so anyone who know how to use a regular gun could in a few hours not master the gun but at least be a better option than Snart.

You're right Snart wasn't even showed to be an essential part of the plan. They say that they needed him but we don't even know why. His presence makes even less sense.

It's true but to ask the help of Snart who was most likely gonna screw them doesn't sound like a better option. Snart being an essential part of the plan seems more like something that is gonna backfire than creating a gun than gonna be used once then destroyed.

It seems weird that they needed Snart because they only needed the gun. Cisco already build Snart gun twice. So why Cisco didn't build an other gun ?