Broken, bland, and bad are the kindest things I can say about Mr. Driller Online.
There is little strategy here, you pick on of several characters, most of whom have pretty useless abilities and are then set loose on your choice of a number of locations to begin your digging adventure. Don't assume this means there's some genuine variety, because there isn't, it's just a slightly different wallpaper, where everything else is recycled, and of course the only objective is to go downward as fast as you can as far as you can.
Power ups are especially helpful when you can't even find any instructions on what they do, even online. This is unpolished Xbox Live Arcade shovel ware at it's finest in that it manages to offer nothing new, and the stuff it rehashes wasn't exactly gaming gold to begin with. It's simplistic, ugly, annoying, noisy, and most egregiously of all, it is just flat out not fun to play. Shame on you, Namco.