Here is the full list of all 12 RISK Factions achievements.
Win 10 online ranked games
Win a 5 player online ranked Command Room game
Achieve 10 super overkills
Win a game on each map
Kill 100 human, cat, robot, yeti and zombie units
Play 5 games online
Defend a minimum of 5 attackers with 1 defender
Control 5 capitals
Defeat someone in online multiplayer who has earned the Man Up! achievement
Complete the human, cat, robot, yeti and zombie campaigns
Earn 10 stars and trade them for 30 troops
Be the first to get an objective in a game