First of all, I would like to say if you've never played Super Smash Bros. Melee, go buy it and do so now, I'll wait.
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Done? Good. That was a really great game. But Brawl has surpassed it in every way and then some. Everything from the graphics to the unlockable content to the addition of online play makes this not just the greatest Wii game, but perhaps the greatest game of all time.
It's an insane fighting game in which you play as characters from virtually every Nintendo Series imagined, and anything could happen with all the items and interactive stages.
Gameplay
Man, where do I start? I guess I could start by saying that there's easily over 100 hours of content in here. There's 35 characters (including Snake and Sonic), 41 stages with a create your own stage option, and over 1000 unlockables, including trophies, stickers, and the new Chronicle. The Chronicle is a timeline of nearly all Nintendo games and when they came out. It's totally useless, but it's still executed wonderfully. The Masterpieces are demos of old games. Also totally useless, and the demos are way too short (you get 30 seconds for F-Zero), providing the only low point of the game. I should go into detail from here on, though.
Subspace Emissary
While the Adventure mode in Melee was just a beefed-up Classic Mode, the Subspace Emissary is a full-fledged, Castlevania-style adventure that you unlock all the characters in. You go through levels in a side-scrolling adventure in which most of the Nintendo characters are trying to fight a very dangerous evil. At the end of the level, you usually must fight bosses from previous Nintendo games (Meta Ridley, Petey Pirhana, etc.). There's also a way to upgrade your characters in that mode using the stickers you can get throughout the game. There's even a Co-op mode.
One Player Modes
If you did what I said to do and played Melee, then this will come as no suprise. Classic and All-star modes have returned. In Classic Mode, you just fight enemies across 12 stages with the rules changing a little bit every time. In All-star mode, you must defeat every character in Smash Bros. with only one life (on the hardest difficulty? Good luck). There's also Stadium mode, in which you do 3 activitiese for the highest score. That one wasn't my favorite. The one-player modes would be weak compared to Multi-player if it wasn't for the Subspace Emissary.
Multiplayer
As any Smash veteran would know, this is the ultimate party game (yes, even better than Mario Party, the original party game). You can adjust the rules of the fight any way you want. And the game's 1-4 players per fight. In rotation mode, you can have up to 16 players taking turns in groups of 4 fight, and Tournament mode supports 32 players in a classic Smash tournament (down from 64 in Melee. Oh, well. Were you really going to have 64 people in the room, anyway?), ensuring the greatest party gaming experience to date. There is also Online play, but I can't give it a score because I don't have Wi-Fi. *cry*
Items
The items are the best part of the game. There's over 100 items that can land on the stage at any time. They range from a Super Mushroom (make yourself a giant) to a Poke Ball (A random pokemon comes out and helps you for a little while). This is what made the past games and this one truly insane.
Stage Builder
Possibly my favorite new addition to Smash Bros. is the Stage Builder. You can use many of the parts seen in the game, choose from 3 backgrounds, and can choose which song to put on the stage. I love this, but more creation options would've made it even better.
Unlockables
This is what really launches the game sky-high. There's over 500 trophies and 700 stickers to collect. In addition, there's the all new Challenges mode, in which you get hints as to how to unlock the thing in the window (ex. Brawl 3 times on Luigi's Mansion). However, to unlock the hint, you must unlock the thing in the window next to it. Like I said, over 100 hours easily.
See? I could've just put all that in the Gameplay paragraph. Aren't you glad I didn't?
Graphics
Whoa! Is that an Xbox 360 I see before me? These graphics are so detailed and textured, that you might wonder. Unfortunately, the Melee stages haven't been updated, leaving some graphic dust on those stages, and, sadly, avoiding the 10. Rats...
Sound
Let me put this simply. There are over 200 songs in the game, including Star Wolf, the Mario Bros. 3 theme, and the Metroid ending. They are either redone great or the amazing original soundtrack. You get songs by collecting CDs as they appear on the stage. And the voiceovers are great as well.
Control
Even the often overlooked controls are done masterfully. The controls are simple and easy to understand. There are even 4 controller options to choose from the Wii Remote, the Wii Remote and Nunchuk, the Classic Controller, or, the Melee veteran's favorite, the Gamecube Controller.
This game is so jampacked with content, I had to dedicate 7 paragraphs to the gameplay. This is easily the best game released on Wii so far, and it will keep you occupied for a very, very long time:)

The Wii is now a retro console. Let’s get nostalgic about an often maligned system.
Crazy to think the WII is to the Switch 2, as the NES was to the WII back then. 20 Year difference.
My wife asks me to bust it out (heh) everyone once in a while to play bowling and tennis with the kids. There was a ton of slop on it but some good stuff as well.
Wii was great but boy howdy did it cause Microsoft to go on a dark walk with the Kinect and the disastrous XBox One launch that they arguably never recovered from.
Not nostalgic for me.. I was there.. anyone who wasnt a little kid realized it was a gamecube with shit tacked onto it, it was the "joke" system and was well below even the switch in terms of comparing it to the latest machines at the time. The machine was well loved by young people and "casual gamers" who now remember it 20 years on, or in most cases more of its sales came in the 15-20 years ago range not right at launch- but again its not nostalgic for people who were "gamers" then really, just for those who ended up with one in their house, the games , graphics, interface and online features were archaic already in 2006.

All of the Super Smash Bros. games are incredible, but which one stands as the mightiest of them all and has the best modes?
To me smash brows Melee is my all time favorite. I can't tell you how many hours I played that game between friends and family. When I was a kid, my parents couldn't afford a gaming console so I had to go somewhere that had an arcade like setup with the only difference being instead of arcade cabinets, they had big screen crt TV's and gaming consoles setup. I would go with my friends on special occasions after school or with my family on the weekends.
I would meet and make new friends at that place as we were all gamers and we also brought our game boys and would trade pokemon. I don't think those places exist these days but back then, it was easy to meet like-minded people and have fun for hours.
Well, I’ll add my extremely subjective ranking too. I won’t include the 3DS version as I don’t owned it. I did play it for a few minutes though.
5. Brawl.
4. N64 Smash
3. Ultimate
2. Wiiu Smash
1. Melee

Sakurai's views on cutscenes (and how quickly they'll be shared online) haven't really changed that much in 16 years.
The graphics are more like melee 1.5 and are not anywhere near 360 graphics. That being said, I really don't think the graphics are that important in a fighting game. It is the gameplay that is paramount. Gameplay is also where brawl falls flat on its face. The action has been completely dumbed down and slowed compared to melee.
Many "advanced"(L-Canceli ng) tactics have become automated or abandoned(wave dashing). This was probably done in order to appease more "mainstream" gamers but really it has only hurt the more competetive crowd. In melee no one was FORCED to use these tactics but now they are gone or automated, bridging the gap between beginners and "hard core" players. There are still plenty of mind games to be had but most technical players are out of luck. That combined with terrible character imbalances (most fighters have imbalances but brawl really stands out here) and easy to abuse infinites or just plain really easy, cheap, tactics are easy to be found. Also, the fast action of melee is slowed down to where veteran smashers will think there is something wrong with their TV or controller (ok not that bad but WOW IT IS SLOW).
The music is good (it s a fighting game who cares???) and the fun factor might be high for newer or casual players, but anyone who wants to dig deep into this game will find that all the mechanics are very shallow and they will likely be bored within a couple of weeks as they discover imbalances and character shortcomings. Brawl is not THAT BAD of a game, but it certainly does NOT FILL THE SHOES of melee.
This game was just an upgraded melle and nothing more. Melee was actually better becuase it didnt do that casual gaming crap. That ruined brawl.