These mechs are iterations of the same design. So in the world I was creating here zombies have overrun the planet, fortunately, the tides are turning and we are slowly getting back our cities and towns. In an effort to avoid dropping nuclear bombs and causing more damage or killing innocents still in hiding the military has developed the Zombie Extermination Unit or Z.E.D. for short. This unit is specially trained and equipped to hand the zombie plague.
The mech above is basically a bait mech. It squirts out fresh blood and plays loud music to draw out any zombies. The cockpit has small openings to allow for the scent of a human to travel through the air. Zombies have gotten a little smaller and do not respond to corpses. As the zombies come out and the surround the mech net guns shoot and capture some of them for experimentation, the others it just saws through or deploys thermite bombs and walks away for remote detonation.
I will post some of the iterations later as well as the vehicle that accompanies this unit. Hope you like!