Here is the full list of all 69 Dragon Age Inquisition achievements. It takes around 80-100 hours to unlock all of the achievements on Windows.
Craft an item from Tier 4 materials in all non-masterwork slots in single-player mode.
Enter the heart of the Solasan temple.
Rub Some Dirt on It on: slay the Hivernal high dragon.
Kill a high dragon in single-player mode.
Even Ground on: slay a level 16 or higher Fereldan Frostback.
End the threat once and for all.
Finish the single-player campaign on at least Hard without lowering the difficulty.
Finish the single-player campaign on Nightmare without lowering the difficulty.
Reach an ancient ruin before your enemies.
Reach level 20 in single-player mode.
Unlock 15 astrariums in a single playthrough.
Liberate three keeps in a single playthrough.
Defeat 2,500 enemies in single-player mode.
Complete 20 requisition requests in a single playthrough.
Discover a campsite and establish at least one Inquisition camp in 10 wilderness areas.
Slay 10 great bears promoted by Grizzly End.
Acquire 10 Inquisition agents in a single playthrough.
Earn 50,000 or more gold across all single-player playthroughs.
Level up the Inquisition to rank 10.
Upgrade your alchemic potions, grenades, or tonics 30 times in a single playthrough.
Face your fears in the Fade.
Spend 10 points in a single ability tree with any one single-player character.
Commit to a romantic relationship.
Become friends with at least three of your inner circle in one playthrough.
Make an impression on the Orlesian court.
Gain the full approval of the Orlesian court.
Harvest 50 herbs from Skyhold's garden in a single playthrough.
Choose a specialization class.
Defeat 20 foes promoted by Walk Softly.
Land a single blow in excess of 1,000 damage in single-player mode.
Purchase any new decoration element for Skyhold.
Completely upgrade one throne.
Survive an attack on the Inquisition.
Collect 250 codex entries in a single playthrough.
Recruit all possible companions in a single playthrough.
Close the Breach.
Complete 50 missions or operations in a single playthrough.
Purchase or secure five different mounts of any kind.
Recruit a new companion.
Gain access to a major city for the Inquisition.
Discover a veilfire rune.
Find and recover a shard identified by an ocularum.
Upgrade any ability once in single-player mode.
Finish the prologue.
Craft a weapon or piece of armor in single-player mode.
Enchant or upgrade a piece of equipment in single-player mode.
Complete a timed mission on the war table.
Discover a campsite and establish an Inquisition camp in any wilderness area.
Secure a mount.
Trigger a cross-class combo with a character you control in single-player mode.
Recruit a powerful ally to even the score.
Slay 10 high dragons in single-player mode.
Defeat 1,000 demons in single-player mode.
Seal 75 rifts in a single playthrough.
Destroy all the Winter Shards and light all the fires in the Old Temple.
Impress the Avvar of Stone-Bear Hold and gain their friendship.
Uncover the secrets of a legendary figure.
Dispel a myth of ancient days.
Complete a mission at the expedition table in the Legion of the Dead camp.
Defeat an ogre alpha.
Help Shaper Valta discover secret dwarven history.
End the earthquakes threatening the surface.
Rest Easy trial always on in Emprise du Lion: claim Suledin Keep.
Travel Light on for "In Hushed Whispers": finish the quest.
Take It Slow on: reach Skyhold at level 5 or less.
Fair-Weather Friends always on: enter Halamshiral with all followers.
Progress the story to unlock.
Unlock all caches watched over by ancient statues.
Find all of the wearable items that make up the Taken Shape.