From their website:
Today we present another preview for Battles of Westeros, courtesy of lead designer Rob Kouba. In our earlier previews, we’ve looked at combat, terrain, and troop management. Today, we’ll catch a glimpse of the game’s various unit types.
As a commander, your tools on the field of battle are your units. Each House in the Battles of Westeros has a total of four different unit types, and three of the unit types for each House are the same. However, each House also has a special unit type.