Not every game needs upgrades. Sometimes I don't want to play an RPG. I appreciated the arcade style of this game, and if the diggers "stats" are inadequate, then I propose simply getting better at the game instead of simply playing long enough to progress. This is not WOW.
I liked it. I mean, the game play could have been more... interesting, but I thought the story was unapologetic in it's message. The thing about really stylized things like this is some people are going to love it, others are going to... hate it. It's all a matter of opinion, but mine is good.
 "Magi: The Fallen World"){kind=icon}
 "Chisel"){kind=icon}
 "Flaming Zombooka"){kind=icon}
 "Loondon"){kind=icon}
 "Hexiom"){kind=icon}