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.
Collect 15 Red War exotic weapons or armor.
Encounter an Agent of the Nine somewhere in the system.
Complete a Flashpoint on Earth, Titan, Nessus, or Io.
Complete a Nightfall strike.
Complete Introduction: Crucible.
Complete a Heroic public event.
Acquire each Warlock subclass.
Acquire each Hunter subclass.
Reach level 20.
Acquire each Titan subclass.
Complete the Leviathan raid.
Complete the Leviathan raid on Prestige difficulty.
Collect 10 Forsaken Exotic weapons or armor.
Complete a Collections Badge.
Complete a Forsaken Exotic Quest.
Win a Gambit match.
Pursue Uldren and the Fanatic to the Watchtower, and finish what you started.
Earn 5,000 Triumph points.
Enter the Dreaming City.
Complete a Triumph Seal.
Defeat a Forsaken Nightfall Boss.
Complete the "Last Wish" Raid.