Here is the full list of all 50 Guitar Hero: Smash Hits achievements worth 1,000 gamerscore.
You completed the song Raining Blood with 5 stars as the Drummer on Expert+.
You completed the Career Tutorial.
Get 5 stars on the song Beast And The Harlot as the Drummer on Expert without using Star Power.
You got 100% on a song as a Band (4 players).
You scored 2,000,000 points on Free Bird as a Band.
You completed the Career in a Band (2-4 players).
You completed a song with all Band members on Expert (4 player Band).
You won 50 online matches.
You won a Band vs. Band match (8 players).
You played 20 online matches.
You completed single player Expert Career on all instruments.
You completed all four instrument Careers on any difficulty.
You completed the Career as the Drummer.
You completed the Career as the Vocalist.
You played 150 songs throughout your entire Career.
You completed the song Through The Fire And Flames with 4 stars or more as the Guitarist on Expert.
You completed the song YYZ with 5 stars on Expert Bass.
You completed the Career as the Guitarist.
You completed the Career as the Bassist.
You completed a song in every venue.
You won an online Face-Off match by 25,000 points or more.
You got a 100 note streak in the song Through The Fire And Flames on Hard or higher as the Drummer.
You won an online Face-Off match.
You won an online Pro Face-Off match by 25,000 points or more.
You won an online Pro Face-Off match.
You played a song in the Atlantis venue.
You triggered Star Power simultaneously (4 player Band).
You scored the highest individual score in a 4 player Band.
You completed a song in a Band (4 players).
You completed a song on Expert + (Drums only).
You performed as the Drummer.
You completed the song Smoke On The Water as the Vocalist.
You completed 100% on any song on Expert in single player.
You performed as the Vocalist.
You won a song with the rock meter in red.
You performed as the Guitarist.
You scored 5 stars in a song on Expert with Lars Umlaut in single player.
You failed a song with available Star Power in single player.
You recovered from a poor performance.
You performed as the Bassist.
You completed a song with any instrument on any difficulty in local Quickplay or Career.
You downloaded a song from GHTunes(SM).
You created a new custom Band logo.
You created a new custom rocker.
You created a new custom instrument.
You created a custom tattoo.
Score 95% or more on the song Killer Queen as the Vocalist (Expert).
Hit all Open Strum notes in the song Laid To Rest as the Bassist.
Perfectly play the Let's Play! section in the song Play With Me as a lead Guitarist on Expert.
Perfectly play the First Blood section of Raining Blood as the Guitarist on Expert.