Sonic Adventure is probably Sega's first attempt at bringing the Sonic universe into 3D, not including things like Sonic 3D Blast or Sonic Jam. While it does show its age in some areas, it holds up very well, and still manages to be a very enjoyable experience.
The first thing interesting about this game is that you're given the ability to play as 6 different characters, which consist of Sonic, Tails, Knuckles, Amy, E-102 Gamma, and Big... while some of them offer different playstyles, they are there mostly to extend playtime. You start the game as Sonic, and as you meet other characters in the story, you'll unlock them afterwards.
- Sonic's gameplay consists of running through the stages at fast speeds, and doing some simple platforming to reach the goal. His controls very smooth and responsive.
- Tails' gameplay is very similar to Sonic's. You basically control similar to Sonic, but are granted the ability to fly for short periods of time. His levels are smaller sections of Sonic's levels, and usually consist of racing Sonic to the goal.
- Knuckles plays completely differently. His stages consist of finding 3 pieces of the Master Emerald. You are thrown into a small restricted area of a stage, and you have an indicator telling you how close you are to the pieces.
- Amy's gameplay is very similar to Sonic and Tails' gameplay, but the levels have you running away from one of Eggman's robots known as Zero. If he catches you, it's a game over. The levels are essentially the same, but smaller, and have a few different paths to take.
- E-102 Gamma is very interesting compared to the other characters. His gameplay feels rather out of place, not as out of place as say, Big. But we'll get into that later... E-102 is one of Eggman's very own creations, you go through levels aiming at targets and shooting through the stages. At the end of each stage, there is a mini boss battle where you fight another robot from the 'E' series.
- Big is probably the biggest oddball in the entire game. Definitely my least favorite of the bunch. His gameplay consists of fishing. Yes, you heard me right. Fishing is what you do here. Big has lost his best friend, a frog named Froggy, who happens to have swallowed a Chaos Emerald. You go through stages fishing for him. You can collect points by getting other fish, but the main goal is to get Froggy.
- Other than these major gameplay types, you'll sometimes be thrown into a sub game. These sub games mix up the gameplay a bit.
In order to get to the final boss of the game, you must beat all of the characters' different stories. Which I do not enjoy that much. Sonic, Knuckles and Gamma's stories are fine. They all offer something unique, and mix up the gameplay nicely. But Tails and Amy are near identical to Sonic, with minor tweaks. And Big is completely out of place. Yes, he does also offer something 'unique'. But it's not even platforming, it's fishing. It can sometimes be frustrating capturing Froggy, as there are a ton of other fish in the water, and if you mess up, you lose a life.
Every stage has 3 different goals, which each offer you something known as an 'emblem'. The game's reward system of sorts. There are also 3 different major hub worlds, which provide a lot of exploration, and connect the levels. Although, they do feel a bit barren at times. Emblems can also be found here, there are 12 total. Sub games also offer you an emblem for completion. Collecting all 130 emblems will grant you a special reward. I won't spoil it here, but I think it's a little underwhelming for all the work that goes into collecting them all.
The game's story is rather simple. All the characters have their own unique small stories, but they all meet at some point in an even larger story that builds up to the final boss. While it is a tad cheesy at times, it does get you wondering at a few instances, and Gamma's story alone was very interesting.
In true Sonic fashion, the music does not disappoint. This soundtrack features what I would call some of the best tracks in the entire series. There's a lot here too. So many different styles. Every level has a theme, sometimes more than one even! The hub worlds have a unique track, and heck. Each character has their own theme too. But something even greater is the main theme, Open Your Heart, performed by Crush 40. This is the start of awesome theme songs for more Sonic games to come.
In terms of replay value, normally there wouldn't be that much to come back for, other than replaying the stages. But since this is the DX version, there is extra content. First off, there are missions. After beating one of the main stories, you unlock that character in mission mode. Here, you'll be thrown into the hub worlds with total freedom. You'll come across these cards, that give you a specific goal. Once you complete that goal, you will have completed the mission. There are 60 missions total. Every 10 missions you complete, you are awarded with a Game Gear game.
I highly recommend this game. Not only does it feature great gameplay, for the most part. It also has a great musical score, and bonuses to hunt for. While not every gameplay style is great, overall, most of the stages kept me coming back for more. And the story, while a little cheesy, was certainly an adventure alright. If you're a fan of the 2D Sonic games only, this might be the 3D Sonic game to try first. It stays true to the originals in a lot of ways, but makes things feel fresh again.