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

The Maximum (15 points): Score 180 in 3 darts in a non-party match.
Nine Darter (70 points): Finish a leg in 9 darts in a non-party 501 match.
Super flinging (10 points): Finish a leg in 6 darts in non-party 301 match.
Magic Darts (20 points): Finish a leg in 12 darts or less in a non-party 701 match.
Superduper (15 points): Score a 170 (T20, T20, Bull) checkout in a single turn in a non-party match.
Fabulous flinging (15 points): Score a 153 (T20, T19, D18) checkout in a single turn in a non-party match.
Top tungsten (15 points): Finish a leg in 9 darts in a non-party 501 match scoring 167 (T20, T19, Bull) three times.
Bang in the middle (20 points): Score a 150 (Bull, Bull, Bull) checkout in a single turn in a non-party match.
World Championship (40 points): Win the World Championship.
World Grand Prix (30 points): Win the World Grand Prix.
Desert Classic (30 points): Win the Las Vegas Desert Classic.
UK Open (30 points): Win the UK Open.
World Matchplay (30 points): Win the World Matchplay.
German Champ (30 points): Win the German Darts Championship.
US Open (30 points): Win the US Open.
Grand Slam! (50 points): Winning all tournaments in a single year in career mode.
Whitewash (20 points): Win a match against a Pro player without losing a set in career mode.
Perfect Match (30 points): Win a match against a Pro player without losing a leg in career mode.
The Power (20 points): Beat Phil Taylor in Pro or Master difficulty.
Barney (20 points): Beat Raymond van Barneveld in Pro or Master difficulty.
Jaws (15 points): Beat Colin Lloyd in Pro or Master difficulty.
One Dart (15 points): Beat Peter Manley in Pro or Master difficulty.
Hawaii 501 (15 points): Beat Wayne Mardle in Pro or Master difficulty.
The Rocket (15 points): Beat Ronnie Baxter in Pro or Master difficulty.
Jackpot (15 points): Beat Adrian Lewis in Pro or Master difficulty.
The Artist (15 points): Beat Kevin Painter in Pro or Master difficulty.
Darth Maple (15 points): Beat John Part in Pro or Master difficulty.
Hammer (15 points): Beat Andy Hamilton in Pro or Master difficulty.
Rocky (15 points): Beat Andy Jenkins in Pro or Master difficulty.
The Bull (15 points): Beat Terry Jenkins in Pro or Master difficulty.
The Iceman (15 points): Beat Alan Warriner-Little in Pro or Master difficulty.
The Menace (15 points): Beat Dennis Priestley in Pro or Master difficulty.
The Tripod (15 points): Beat Roland Scholten in Pro or Master difficulty.
Flash (15 points): Beat Mark Dudbridge in Pro or Master difficulty.
Highroller (20 points): Achieve a 3-dart average greater than 120 in a single non-party match.
Lowroller (30 points): Achieve a career 3-dart average greater than 100 over a season.
Nobody saw it! (5 points): Score 180 in 3 darts on the practice board.
Going Pro (10 points): Score a 3-dart finish higher than 140 in a non-party match.
Hitman (10 points): Score more than ten 180s in a career match.
And so it begins… (5 points): Win your first non-party match.
Bullshot! (5 points): Finish on the bull in a non-party match.
Number One! (100 points): Be world #1 in career mode with a custom character at the end of the season.
In the game (5 points): Win a ranked match on Xbox LIVE.
Winning streak (20 points): Win 10 ranked matches in a row on Xbox LIVE.
Live and Dangerous (30 points): Win 50 ranked matches on Xbox LIVE.

Additionally, there are two secret achievements, both of which are currently unknown:

Secret achievement (5 points): Unknown.
Secret achievement (5 points): Unknown.