Here is the full list of all 11 Divided We Fall achievements.
Play your first multiplayer battle
Throw 25 grenades
Stun all 4 of a players soldiers with one grenade
Throw 2500 grenades
Hand down 25 weapons to subordinates
Kill an enemy with a 1% shot or lower
Participate in a match with at least 15 players each side.
Throw 25000 grenades
Hand down 2500 weapons to subordinates