Unlike other game re-releases on XBLA, Mr. Driller Online hasn't received much of a visual overhaul. Everything remains faithful to past versions as far as design goes; characters are simple, cute and easily identifiable, while most of the gameworld is made up of multi-colored bricks. Although the backsplashes and menus have a sharp, crisp look, the game itself is blurry. However, this is something that will probably only irk the most hardcore of visual snobs since the gameplay itself is unhindered by the less-than-HD look.

Music has a fun, upbeat feel that keeps you moving throughout the level. It doesn't always match the locales that the levels take place in, but there's enough of a vibe between the two that it still works. Besides, every level ends up looking the same once you get to a certain depth, so it's not like you'll really care once you're 300 meters into the ground.

Mr. Driller Online is a deceptively simple game; choose a driller and begin drilling in a level. Each area is filled with a number of colored blocks that disappear when drilled, which will often cause other bricks to fall down and disappear. If like colored blocks connect, they'll disappear, causing other blocks to collapse, possibly creating long chains of clearing blocks. If a block doesn't disappear, it will keep falling until it hits solid ground, killing your driller if he happens to be standing in the way. As if the pressure of being crushed by heavy falling objects wasn't enough, your driller also has a limited air supply that must be refilled by collecting air supply capsules that are buried in each level.

This premise carries over between the two major single-player modes, as well as the two multiplayer ones. In Standard Driller, you are required to drill to a set depth before running out of lives. Quest Driller further complicates things by requiring that you not only meet certain depth requirements, but also complete various other side tasks every 100 meters. For example, one section may have a set time limit while another requires that you clear a certain number of blocks. The deeper you get, the more challenging the tasks become, adding another layer of gameplay for more advanced players.

Online, Mr. Driller Online supports up to four players in Solo and Tag matches. In Solo games, players race in order to see who can clear the level first. Although everyone can see each other, players can't mess around with each other. Tag games run on the same premise, only players form teams of two and must cooperate. Each team member must collect half of a power-up before it is useable and, if one member begins to run out of air, the other player can share his supply. Both of the online variations are fun, though it is really hard to find games sometimes - though this is turning out of be a common problem with online XBLA games, so aside from making the game free, there's very little Namco can do to fix that problem.

Seeing as how the object in Mr. Driller Online is the get to the target depth as quickly as possible, it makes perfect sense to want to just keep drilling straight down as fast as you can. Actually, this is probably the most common tactic I've seen newcomers (myself included) take and it always ends the same way - dead within the first hundred meters. Mr. Driller Online requires a fair bit of strategy, requiring players to keep an eye on how blocks could collapse and where the safest places to drill are. However, it is also possible to overthink about strategies. At times, it is almost better to "mindlessly think" about tactics and play things by feel and instinct rather than figuring out complex clearing strategies.

Each of the playable drillers has their own Air and Speed ratings. The first determines how quickly their air supply runs out, while the other determines how fast they can move around the level. Each character's ratings balance out (fast movers tend to suck up air faster), though some have special abilities that help put them apart from the pack. For instance, the robot driller can take an extra hit before dying, while another, Taizo (better known as the main character in Dig Dug), clears blocks incredibly fast. None of the abilities make one driller better than another, making it a matter of personal taste and play style.

Overall, Mr. Driller Online is a fun action-puzzler. Even when it feels like too much of a challenge, the underlying gameplay is engrossing and enjoyable enough to keep you wanting to play. Even if you don't make it to the end on the next play, simply getting one layer deeper than before is a rewarding enough experience to make you want to play "just one more game."