Here is the full list of all 39 HELLDIVERS achievements.
Complete a mission.
Kill 7 enemies within a very short time using only your primary weapon.
Customize your character.
Do 25 capespins in a row, without moving, while on the ship bridge.
Finish the Training.
Complete a difficulty 10 or higher mission without a single death.
Kill 100,000 enemies.
Complete at least one planet in a successful Galactic Campaign.
Kill a Bug or Illuminate assassination target by running it over with the APC or HAV.
Achieve the rank of Grand Lord (Rank 25).
Kill a Bug Tank with a Resupply Stratagem Hellpod.
Take part in a successful defense of a capital city by completing at least one mission.
Extract from a difficulty 8 or higher mission with 4 players where all 4 get on the shuttle.
Use the Reinforce Stratagem while downed and the last Helldiver alive on a difficulty 8 or higher mission with 4 players.
Complete a difficulty 4 or higher mission in 5 minutes or less.
Kill 10,000 enemies.
Achieve the rank of Captain (Rank 13).
Take part in a successful final assault on an enemy's home planet by completing at least one mission.
Complete all missions on a planet with difficulty 10 or higher.
Complete a difficulty 7 or higher mission without triggering any alarms.
Successfully complete an escort objective where all 4 NPCs survive.
Complete a difficulty 7 or higher mission against the Cyborgs without taking damage from any enemy.
Complete a mission using only Stratagems.
Complete a mission with over 300 shots fired and 80% accuracy or better.
Join another game through the matchmaking system.
In a 4 player game, on a Friday, have all players sitting in an APC or HAV at the same time.
Achieve the rank of Sergeant (Rank 7).
Play at least once against all enemy races.
Play at least once on a desert, a forest, and a snow planet.
Destroy a Bug Nest, Cyborg AA, or Illuminate Beacon with anything but the NUX-223 Hellbomb.
Fully upgrade all non DLC Weapons and Stratagems.
Kill a Bug Tank, Bug Behemoth, or Cyborg IFV by having the extraction shuttle land on it.
Face each new enemy once.
While in melee range from a Cyborg Warlord, use the "NO" communication command.
Complete a volcanic type planet of difficulty 5 or more.
Kill an Illuminate Obelisk while it is closed.
Defeat a Bug Hive Lord.
Defeat a Cyborg Siegemech.
Defeat an Illuminate Great Eye.