Risk: Factions, as the name implies, offers 4 different factions that can be played.
The Human Faction is the first faction that the player controls.
Unlike Cats and Zombies, the Humans have no defensive weapons, and must rely on their troops alone.
That being said, Humans have access to weapons that greatly increase their attacking power: Cavalry and Steam Tanks.
Humans also have access to the very powerful Donkey Cannon. Which can wipe out a large group of units.
Because their main weapon is defensive and only lasts one turn, Cat players will usually find themselves at a disadvantage in the early stages of the game.
The Zombie Faction plays different and has other upgrades from the other factions.
The Robot Faction Is a new faction coming soon.