So i tried this mech once, But i have a good enough understanding as to how it works.
Round Hammer here specializes in defence and attack, Whilst sacrificing Mobility, He has a electric smoke bomb attack to propel backwards and fend off close targets, A self Destruct to get a kill if he's close enough, A shot gun blast, Wich turns into the particle cannon when Holding the block button. Do note you need to HOLD the attack button to fire said cannon, And of course he comes with the basic assault cannon on his chest
I'd reccomand this guy if you want someone who excels at turteling or if you want a mech that is good for absorbing damage for the team, Since When Round hammer has, as far as i know, has an infinite block duration.
But do keep in mind he's slower then the average mech in every aspect, So if you don't like being slow but nearly unstoppable, You might wanna reconsider