Brutal Legend Immediately

If you are a fan of Jack Black, Tim Schafer (this games developer), Heavy Metal, or highly inventive and unique games you could probably just stop reading this review and go buy the game. The only caveat is what kind of length you expect from a single player experience to justify a $60 game purchase.
I'll do my best to remain spoiler free in the review below, but please be aware that there may be some minor spoiler. You may want to skip to the conclusion if you want to remain 100% spoiler free.

Story:
The story of Brutal Legend centers on Eddie Riggs (Jack Black), a roadie for a faux-metal band (i.e. Angst-ridden teenagers singing shallow songs to a mix of hip-hop beats and electric guitar.) There is an onstage accident at a concert and Eddie is injured, resulting in some of his blood dripping onto his belt buckle. This mysteriously triggers the belt buckle to transport Eddie to another world... a world of heavy metal.
The single-player campaign runs about 6-8 hours.
Graphics:
This game sports some of the most unique, and original visuals of any game I've played. If you are familiar with Schafer's last game Psychonaut's (if you're not, you should be) you will have a pretty good idea of what to expect here. The graphics are tonally similar.
For the years leading up to this games release Tim Schafer continually made reference to how cool the heavy metal album covers of the 80's were, and that his desire is to create a world that looks like you are in a living, breathing album cover. He succeeds on every level. The scenery is diverse and ranges from rolling hills with giant swords protruding from them to volcanoes that flow with molten chrome. The weather changes from sunny to stormy (replete with magenta colored lightning). It all reminded me very much of a Frank Frazetta painting.
One of the most impressive things with the environment is the variety. This is an open world game, but the world never becomes repetitive. The developers obviously spent a great deal of time on making every area unique as there is not an obvious use of repeated textures, and there is not any area that seems generic or bland.
The world is split into different regions based on the different sub-genres of heavy metal. The primary area looks like the classic album covers referred to above, but your adventure takes you through worlds designed around the caveats of "hair" metal (Poison, Twisted Sister, Ratt, etc.), goth metal (Cradle of Filth, Graveworm, etc.), and industrial metal (Metallica, Megadeth, etc.). Each of these regions has enemies and creatures designed specifically for their sub-genre and there is great attention to detail.
The art team for Brutal legend used a full palette of color for their world as opposed to the current trend of desaturation and overloading the scenery with browns and grays. It all comes together to make a beautiful and uniquely intriguing package.

Sound:
The sound design here is good, but not great. The surround effects are solid, and the game soundtrack is very well done. When you are in your car ("The Deuce") the radio comes on and plays from a playlist of approximately 100 heavy metal songs. If you leave your car you the music pans and fades as you move around and away from (or closer to) your car. For those that are not metal fans, you can turn the music off if you'd like.
The sound effects themselves are a little on the weak side. The sounds for your vehicles and some of the animals are very good, but the battle (hack and slash) sounds come across as generic.

Gameplay:
The controls and gameplay are very well designed. Early on you gain a large battle axe as your primary weapon, and you also have an electric guitar.
The axe is used as one would expect; for hack `n' slash gameplay. The axe can be upgraded throughout the game to have different abilities (lightning, fire, extra damage, etc)
The guitar is used for special (i.e. magic) attacks. Initially the guitar will only call down lightning to stun enemies. However, throughout the game Eddie will learn solo's that do various things:
A. Summon your car. This is very much like calling your horse in Legend of Zelda:Ocarina of Time.
B. Area of effect attacks. These are all based on cliché's or in-jokes in the heavy metal community, but they are effectively to give a "Whoa! Cool!" response. There is a heavy guitar riff that melts the faces of all enemies close by. One solo calls down a flaming blimp that explodes over your enemies. There is another that summons a horde of animals to your side.
C. Unit command solos. These solos are used in the "Stage Battles" (see below) to rally your troops, send troops to s certain area, etc.
The gameplay of Brutal Legend is a mash-up of multiple genres. You can explore the world of Brutal Legend in your car (which is upgradeable with weapons, armor, etc.). The driving mechanics are pretty solid and fun in an arcade-y way. You can also explore on foot which leads to the aforementioned hack-n-slash gameplay. However, the major battles are fought in a semi-RTS (real-time strategy) mode called "Stage Fights."
Stage Fights are interesting in that you start with a basic stage (replete with lighting and smoke effects). To power your stage, which allows for building units, you must harness the power of the fans. Fans are found in Fan Geysers. You must locate fan geysers and then build a "Merch Booth" (i.e. Merchandise Booth) over the geyser to draw the fans to your stage. The more geysers you control the more fans you collect. The more fans you collect the more units (and more powerful units) you can build. The units range from Head Bangers (foot soldiers) to Metal Beasts (fire breathing mountable monsters). Your goal is to steal your opponents fans, and ultimately destroy their stage.
The reason I call this a semi-RTS is that it is a mashup of all three play modes in itself. As you build your units and send them into battle you can also jump into your car or run into battle yourself. It is not an RTS where you build units, send them into battle and just watch the results... unless you want it to be. I found it much more fun to build units and then lead the charge.
All of this sounds a little weird, right? Welcome to the world of Tim Schafer! The gameplay is so unique in the way it blends playstyles that I am sure I had a big dumb grin on my face for most of the game. It is not often that you find a game that is this ambitious about its gameplay mechanics, and actually succeeds at building something that is not frustrating, but fun. It is so good, that I am almost compelled to overlook the shortcomings of the gameplay, but I will go ahead and mention them anyway...
The oddest thing missing from the gameplay (given all of its depth) is that there is no jump button. That's right, this is an openworld game that allows you to run freely through a streaming (read: no load time) environment, but you can't jump over or onto anything. Granted, the world is designed in such a way that jumps are not a necessity to navigate it, but (if you are like me) for those that like to really explore and go off the beaten path it would be nice to be able to jump. Also, there were a couple of times that, after an unfortunate incident in my car, I wound up stuck between boulders or trees. Without the ability to jump out of the situation I was forced to go to the menu and reload my last checkpoint.
Also missing is a HUD that shows you your health status, etc. I understand this exclusion as it could detract from the immersion into the amazing world that has been built for this game. However, it would have been nice for it to at least be optional, or perhaps only show up when you are in combat. There were numerous times that I would have no idea my health was getting low and I was suddenly dead. There are visual cues such as the screen starting to go red, etc. as your health is depleted, but as you get further into the game you begin to come across enemies that can apparently kill you with one or two hits (before the visual cue kicks in).
The multiplayer in the game is based on the Stage Fight idea mentioned above. You and your opponent select a metal faction, build a stage, and battle it out. The single player campaign serves as a robust tutorial for how to play the multiplayer game, and does so very well.
Innovations:
See Gameplay (Above).

Final Thoughts:
This is a VERY fun game. Even if you aren't into heavy metal (which I am not) you can enjoy this game, and even get most of the in-jokes. There is not much in the game to criticize as it shows a lot of polish and fulfilled ambition.
I only wish the single player campaign were a bit longer. If you go straight through you can complete the single player portion in under 8 hours. If you work through all of the side quests I would estimate the games length at about 13-15 hours.

I should also state that I have played this game on both Xbox 360 and PS3. For some reason the PS3 suffered from some serious frame-rate issues at times. The most confounding thing is that the issues popped up just as I was standing still looking around the landscape, and not so much when there was a lot of activity onscreen. Hopefully there will be a patch for this soon, since I didn't experience any lag or frame-rate dropping on the 360 version.
NOTE: This game does not lack for profanity and gore. It is chock full of both. However, you do have the option of turning either or both off in the setup menus. This removes all blood and dismembering and replaces all curse words with "bleep" sounds. It also places a parental advisory (as seen on cd's with explicit lyrics) over any middle fingers and curse words found in the subtitles, which is actually pretty funny.

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