Here is the full list of all 32 Steam Squad achievements.
Protect Usogorsk city.
Kill your first enemy.
Complete Hot-Seat multiplayer game.
Complete first campaign.
Complete second campaign
Complete third campaign
Complete fourth campaign
Complete fifth campaign
Complete sixth campaign
Kill 100 enemies
Kill 1000 enemies
Lost 10 own soliders
Lost 100 own soliders
Destroy 100 units of enemy vehicles
Finish 300 missions
Level up soldier to captain level
Complete all campains losing no more than 10 people
Destroy 100 buildings
Kill 100 cows
Kill 10 enemies using support artillery
Use time bomb to kill an enemy
Make 10000 shots
Finish first campaign without casualties
Finish third campaign with less than three casualities
Finish fifth campaign with less than two casualties
Finish sixth campaign with less than four casualities
Finish second campaign with less than three casualties
Finish fourth campaign without casualties