Full list of all 30 SoulCalibur II HD Online achievements worth 400 gamerscore. It takes around 10-12 hours to unlock all of the achievements on Xbox 360.
Ten Ring Out Victories
Successful Guard Break
Purchased New Weapon in Weapon Master Shop
First Trial Point Cleared in Weapon Master
Guard Impact Triple Success
Victorious over Inferno in Arcade
Ten Successful Counter Hits
Unlock All the Achievements
Unlock All Characters
Three Successful Soul Charge Hits
Ten Victories in Extra Survival Death Match
Victorious in Sudden Death
Standard Time Attack Cleared
Team Battle Cleared
Five Successful Throw Escapes
Used Guard Impact against a Guard Break move
Twenty Perfect Victories
Ten Thousand Hits
Acquired Complete Soul Edge in Weapon Master
Acquired Soul Calibur in Weapon Master
Became Lv 6 "Platinum Neophyte" in Weapon Master
Became Lv 40 "Gold Mercenary" in Weapon Master
Became Lv 72 "Iron Edgemaster" in Weapon Master
Obtained New Costume in Weapon Master Shop
Obtained All Weapons in Weapon Master
Defeated 50 Male Characters
Defeated 50 Female Characters
First Victory in Online Mode
Won 5 Times in Online Mode
Fought 10 Times in Online Mode