Accomplish the indicated achievement to get the corresponding number of Gamerscore points:

Apprentice (10 points): Finish Mission 28 without being discovered by anyone.
Footsoldier (10 points): Finish Mission 8 with at least 90 seconds left.
Genin (10 points): Finish Mission 21 with at least 60 seconds left.
Neophyte (10 points): Finish Mission 1 without being spotted by anyone except Echigoya.
Chunin (15 points): Finish Mission 26 without taking any damage.
Jonin (15 points): In Solo-play do a 20-hit combo.
Oniwaban (15 points): In Solo-play do a 15-hit combo.
Spy (15 points): Without taking any damage finish Mission 11.
Expert Ninja (20 points):Unlock Kagura.
Veteran Ninja (20 points): In Solo-play do a 25-hit combo
Master Ninja (25 points): Unlock Onikage.
Legendary Ninja (35 points): Unlock ALL available characters.