Spirit-X

Unlockable: Legends

Bam Bam Bigelow: Get the Unforgiven Trophy
Bret Hart: Get the Survivor Series Trophy
Cactus Jack: Get the SummerSlam Trophy
Dude Love: Get the SummerSlam Trophy
Hulk Hogan: Get the WrestleMania Trophy
Jerry "the King" Lawler: Get the No Way Out Trophy
Mankind: Get the SummerSlam Trophy
Mr. Perfect: Get the Backlash Trophy
Shane McMahon: Get the Armageddon Trophy
Stone Cold Steve Austin: Get the the Royal Rumble Trophy
Tazz: Get the No Way Out Trophy
The Anvil Jim Neidhart: Get the Survivor Series Trophy
The Rock: Get the WrestleMania Trophy

Secret Achievements:
When you first look at the XBL Achievements for the game, there are six "secret" achievements to unlock. Here they are, and how to obtain them:

Let The Creative Juices Flow (5pts): Create one original Superstar using the Create-A-Superstar mode.
Crown Us The Champ! (10pts): Create a Tag Team Championship in Create-A-Championship mode.
Mr. PPV (5pts): Create an original PPV event in Create-A-PPV mode.
With Friends Like These (5pts): Create an original stable of Superstars in Create-A-Stable mode.
Self Anointed Champion (10pts): Create a singles Championship in Create-A-Championship mode.
Curtain Call (5pts): Create an original entrance in Create-An-Entrance mode.

Unlockable: Unforgiven Arena
You must get the Unforgiven Trophy in Season Mode.

Unlockable: Million Dollar Championship
Finish the Legend Challenges.

Unlockable: DX Tag Entrance
Get the Vengeance Trophy.

Hint - Easy Season Mode:
Plug in a second controller and interrupt the season mode fights. Click multiplayer and simply bash n' pin the "cooperative" second player and win the match!

This also works for General Manager mode; the only disadvantage you have would be the challengers, because you can't do what you could in WWE 2006 (use exhibition mode) and instead you have to do them straight from your locker room (Direct Challenge).

For those who are wondering what is in store for you after you beat the first two sets of challengers (Amateur and Legend tiers) the special challenge is that you have to be MICKIE JAMES and defeat THE GREAT KHALI. Good Luck!

Hint - All 3 Season Achievements In One Go:
Start a Season mode in any difficulty and play through it like normal. After the Unforgiven PPV, save your game and continue to next week. The credits will then start to roll and you will get an achievement for season completion.

During the credits, return to your Xbox Dashboard by pressing the Guide button and selecting "dashboard". This lets you reset and start the game over after earning your achievement.

Go to season mode and select continue. Before continuing to next week, change the difficulty setting to something else and then select continue week. You will then get another achievement. Proceed to do this one more time for the last seasonal achievement.