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

Grade "Novice" (100 points): Get a "Novice" grade in a ranked match.
Grade "Rounder" (100 points): Get a "Rounder" grade in a ranked match.
Grade "Hi-Rounder" (100 points): Get a "Hi-Rounder" grade in a ranked match.
Score Attack Clear (Changpo) (25 points): Clear score attack mode with Changpo.
Score Attack Clear (Cuilan) (25 points): Clear score attack mode with Cuilan.
Score Attack Clear (Ernula) (25 points): Clear score attack mode with Ernula.
Score Attack Clear (Fabian) (25 points): Clear score attack mode with Fabian.
Score Attack Clear (Karel) (25 points): Clear score attack mode with Karel.
Score Attack Clear (Lili) (25 points): Clear score attack mode with Lili.
Score Attack Clear (Mika) (25 points): Clear score attack mode with Mika.
Score Attack Clear (Sakurako) (25 points): Clear score attack mode with Sakurako.
Story Clear (Changpo) (30 points): Clear story mode with Changpo.
Story Clear (Cuilan) (30 points): Clear story mode with Cuilan.
Story Clear (Ernula) (30 points): Clear story mode with Ernula.
Story Clear (Fabian) (30 points): Clear story mode with Fabian.
Story Clear (Karel) (30 points): Clear story mode with Karel.
Story Clear (Lili) (30 points): Clear story mode with Lili.
Story Clear (Mika) (30 points): Clear story mode with Mika.
Story Clear (Sakurako) (30 points): Clear story mode with Sakurako.

Additionally, there are six secret achievements, one of which remains unknown:

1 hour (10 points): Play over 1 hour.
10 hours (30 points): Played over 10 hours.
30 hours (50 points): Played over 30 hours.
100 Hours (100 points): Played over 100 hours.
100 Ranked Matches (20 points): Fought in 100 Ranked Matches.