Here is the full list of all 26 Dead Maze achievements.
Discover a treasure among an infected horde
Reach level 5 Threat
Complete 30 daily missions
Party with other players
Witness an emergency meeting
Reach level 30
Find out what's threatening Lakeview
Craft 30 items
Rescue another player 20 times
Deal with the Outrunner with Jared
Find Egon
Blow up a cafeteria
Meet Jay
Trigger an elemental combo 30 times
Complete the tutorial
Find a place to settle
Reach level 10
Find a roommate
Complete 10 Adventures or Expeditions
Build 30 buildings
Reach maximum quality for each type of clothing gear
Equip a protection kit
Complete 5 adventures or expeditions in maximum difficulty
Reach level 100
Kill 20 infected Peruvians
Kill 5 infected only with the explosion of an unstable infected