Here is the full list of all 54 Spiral Knights achievements. It takes around 200 hours to unlock all of the achievements on Windows.
Alchemize a 4 star item.
Power up a derelict Mecha Knight.
Amass 5 shields in your Arsenal.
Complete a Tier 1 expedition without having to revive.
Alchemize a 3 star item.
Alchemize 50 items.
Defeat the Royal Jelly squatting in the Royal Jelly Palace.
Amass 3 shields in your Arsenal.
Alchemize 25 items.
Earn clearance to explore Tier 2 of the Clockworks.
Amass 10 swords in your Arsenal.
Alchemize a 2 star item.
Alchemize 10 items.
Amass 5 helmets in your Arsenal.
Amass 5 armors in your Arsenal.
Alchemize 5 items.
Amass 3 bombs in your Arsenal.
Obtain a Firecracker bomb.
Amass 5 guns in your Arsenal.
Defeat the fabled Snarbolax that lives deep within the Gloaming Wildwoods.
Revive a downed party member.
Alchemize a 1 star item.
Amass 3 helmets in your Arsenal.
Use 10 Remedy Capsules.
Amass 5 swords in your Arsenal.
Amass 3 guns in your Arsenal.
Use 10 Health Capsules.
Pay a visit to Moorcraft Manor.
Revive yourself.
Reach the first Clockworks Terminal.
Cross the chasm into Haven.
Amass 3 swords in your Arsenal.
Amass 3 armors in your Arsenal.
Successfully reach the Rescue Camp.
Pay a visit to Emberlight, the town of gremlin outcasts.
Earn clearance to explore Tier 3 of the Clockworks.
Descend to the Core Terminal.
Defeat Lord Vanaduke in the heart of the Firestorm Citadel.
Alchemize a 5 star item.
Amass 10 guns in your Arsenal.
Amass 5 bombs in your Arsenal.
Amass 10 bombs in your Arsenal.
Amass 10 helmets in your Arsenal.
Amass 10 armors in your Arsenal.
Amass 10 shields in your Arsenal.
Amass an Arsenal that includes a 5 star helmet, armor, shield, gun and bomb.
Build an item to heat level 10.
Unlock and fill every equipment slot.
Complete a Tier 2 expedition without having to revive.
Complete a Tier 3 expedition without having to revive.
Travel the entire Clockworks from depth 0 to depth 29 in a single expedition.
Travel the entire Clockworks from depth 0 to depth 29 in a single expedition without having to revive.
Defeat the Roarmulus Twins.
Hit an opponent with a snowball in Lockdown.