Here is the full list of all 38 HELLDIVERS 2 achievements. It takes around 50-60 hours to unlock all of the achievements on Windows.
Complete at least 100 missions.
Upgrade all ship modules at least 1 level.
Have 6 orbital barrage stratagems in the same place at the same time.
Shoot off both arms on a Hulk and then extract while it's alive.
Reach max level on one ship module.
Kill 25 enemies with one stratagem.
Kill 100 enemies using fire damage during the same mission.
Complete a full Extreme difficulty Blitz mission and extract in under 6 minutes.
Extract at least 15 rare samples from a mission as a team.
Play a planet defense mission.
Be injured in all limbs at the same time.
Play at least 50 missions.
Kill 5,000 enemies.
Fire at least 150 rounds in one burst, killing at least 10 enemies.
While using a jump pack, knock yourself into a ragdoll state.
Extract with at least 15 common samples.
Kill a Charger with a resupply pod.
Complete 10 tactical objectives.
Complete an Extreme difficulty mission or higher without anyone dying.
Kill a target at a distance of over 100m.
Defeat a Bile Titan
Throw back a live grenade.
Complete a full Hard difficulty mission or higher without anyone firing their primary or support weapon.
Play 1 Bot Mission.
Defeat a Hulk.
Extract with a full team on a Hard difficulty or more mission.
Heal another player using stims.
Complete a mission but fail to extract.
Kill a bug warrior with a shotgun within 1 meter.
Kill 150 enemies during the same mission.
Extract after the timer reaches zero.
Provide assisted reload for a teammate.
Customize your Helldiver with new cape, armor, and helmet.
Play 1 Bug Mission.
Extract from a mission during nighttime.
Complete a Stalker Hive tactical objective.
Fly at least 25 meters from the shockwave of an explosion.
Complete Basic Training.