Full list of all 23 Destiny 2 achievements. It takes around 200 hours to unlock all of the achievements in the base game on Windows.
The base game contains 13 achievements, and there is 1 DLC pack containing 10 achievements.
Complete 30 challenges.
Complete a Flashpoint on Earth, Titan, Nessus, or Io.
Acquire each Warlock subclass.
Acquire each Hunter subclass.
Complete a Heroic public event.
Complete a Nightfall strike.
Complete Introduction: Crucible.
Encounter an Agent of the Nine somewhere in the system.
Reach level 20.
Acquire each Titan subclass.
Collect 15 Red War exotic weapons or armor.
Complete the Leviathan raid.
Complete the Leviathan raid on Prestige difficulty.
Pursue Uldren and the Fanatic to the Watchtower, and finish what you started.
Win a Gambit match.
Earn 5,000 Triumph points.
Enter the Dreaming City.
Collect 10 Forsaken Exotic weapons or armor.
Complete a Triumph Seal.
Complete a Collections Badge.
Complete a Forsaken Exotic Quest.
Defeat a Forsaken Nightfall Boss.
Complete the "Last Wish" Raid.