Full list of all 50 Remnant: From the Ashes achievements. It takes around 35-40 hours to unlock all of the achievements in the base game on Windows.
The base game contains 40 achievements, and there are 2 DLC packs containing 10 achievements.
Defeat the Claviger
Return the Swamp Guardian's heart to the Undying King
Acquire 200,000 scrap
Defeat the Dreamer
Acquire 30 traits
Meet Andrew Ford
Meet the Pan Rebel Leader
Defeat Ixillis XV
Upgrade any weapon to +20
Meet the Swamp Queen
Defeat the Totem Father
Acquire 20 traits
Acquire 10 armor sets
Acquire 100,000 scrap
Defeat a world boss in single player without taking damage
Defeat the Undying King
Meet the Undying King
Defeat 100 special enemies
Meet the Labyrinth Keeper
Acquire 50,000 scrap
Upgrade a boss weapon to 5
Upgrade any weapon to +10
Defeat the Ravager
Defeat the Ent
Acquire 15 weapon mods
Acquire 10 traits
Return ring to Reggie
Upgrade Dragon Heart
Meet the Root Mother
Acquire 5 armor sets
Upgrade any trait to 20
Defeat Singe
Acquire Mudtooth's pocket watch
Upgrade any trait to 10
Return coin to Ace
Acquire 5 weapon mods
Craft a weapon using material from a defeated world boss
Activate the Ward 13 World Stone
Upgrade first weapon
Acquire first trait
Defeat 5 Bosses in a row in Survival Mode
Defeat 10 Bosses in a row in Survival Mode
Purchase 15 Armor Skins
Purchase 40 Armor Skins
Defeat the Final Boss
Listen to all the Recordings in Ward Prime