add wrangler and sentry from TF2, wranger controls sentry, without it sentry is automatic. (can upgrade by hitting with wrench, degrade using electro-sapper)
0rava i think i have an idea if you don't know what people are requesting for.
Go to google and search for what they request, and you don't waste any time.
Idea : The sword from Forbidden Arms (No, don't need all powerups. if you want to add the powerups then put an option in the Options (gear item) on the sword.
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 "Falling Sands"){kind=icon}
 "Kill the Plumber"){kind=icon}
 "Of Guards And Thieves"){kind=icon}
 "Zumbi Blocks"){kind=icon}
A Concuss Power was added in the expansion. It might be hidden by default, and you have to enable it using the Modify List button in the Power Menu.