Guitar Hero: Warriors of Rock Cheats

Gold Master (20): As a single player, earn Gold or higher on three or more Challenges on a single play of a song (QP+)
Gold Standard (20): As a Standard Band, earn Gold or higher on 2 Band Challenges in a single play of a song (QP+)
Hand Mutilator (30): Beat Black Widow of La Porte as a solo Expert Guitarist (QP+, no Powers)
Lucifer's Accountant (10): Beat any song with a final score which is evenly divisible by 6 (QP+)
Manager of Fate (10): Create and play a custom playlist of at least 5 songs, and earn 5 Stars on 5 of the songs (QP+)
Mathematic Sharpshooters (10): Beat any song with a final score ending in 000 as a Band (QP+)
Mocker of Fate (10): Create and play a 5-song random playlist, earning 5 Stars on each song (QP+)
Motivated Improviser (10): Play 100 notes in a single GH(tm)Jam session
Mythical Millionaire (20): Earn 1,000,000 points or more in a single play of a song in a Power Challenge (QP+)
Nauseous Numerologist (10): Beat any song with a final score of 133,337 (QP+, Competitive)
Partial Perfectionist (20): Dominate any 4 chapters of Quest (Earn all the Power Stars from any 4 chapters of Quest)
Patron of the Arts (10): 5-Star any GH(tm)Tracks song containing at least 200 notes (QP+)
Perfect Perfectionist (60): Earn all the Power Stars from all character chapters (Quest)
Player of the Ear Worm (10): Play any one non-GH(tm)Tracks song 10 or more times (QP+, Quest, Competitive)
Poor Boys (10): Beat Bohemian Rhapsody as a band with all on Medium or higher, and at least 2 vocalists (QP+)
Pseudo Perfectionist (20): Dominate any 2 chapters of Quest (Earn all the Power Stars from any 2 chapters of Quest)
Quick Learner (10): Full-Combo any tutorial exercise (no missed notes or overstrums)
Savior of Rock (50): Defeat the scourge of Rock (Quest)
Scions of Excess (20): Earn an 11x Band multiplier with any 4-player Band configuration (QP+)
Seasoned Competitor (20): Play Pro Faceoff, Momentum, Momentum+, Streakers, Do or Die, and Perfectionist at least once each
Self Improver (10): Target your own score on a Challenge and earn a higher grade than you did previously (Local QP+)
Stellar Centurion (20): Deploy Star Power a total of 100 times (Quest)
String Twins (30): Complete a song with only a Guitarist and Bassist, both earning the same score (QP+)
The Brute (20): Release Warrior Lars (Quest)
The Dynamo (20): Liberate Warrior Echo (Quest)
The Eternal (20): Awaken Warrior Axel (Quest)
The Exalted (20): Summon Warrior Pandora (Quest)
The Meek (10): Beat 2112 Part 4 as a Standard band with 3 or more members, all on Medium or higher difficulty (QP+)
The Recluse (20): Invoke Warrior Austin (Quest)
The Siren (20): Recruit Warrior Judy (Quest)
The Trickster (20): Unleash Warrior Johnny (Quest)
The Vigil (20): Charm Warrior Casey (Quest)
Tracker of Deeds (10): Follow any five Hero Feed items (Xbox LIVE only)
Ultimate Answerer (30): Earn all Stars from any one song (excluding the Power Challenge) (QP+)

Spirit Characters
To unlock the Spirit version of a character (as well as their instruments), you must Dominate their section of Quest Mode. When you collect 40 stars on every song in a section, you will unlock that character's Spirit form (basically a white translucent version of their Warrior Form).