Speed
Speed decides how many hexes the unit can move in combat, and the order units move.
Fastest units move first, slowest units move last. When tied, the one that didn't move last within the tie gets to move. Attacker goes first in a tie during first round, defender in all following rounds. Within each army, the unit that started(before Tactics Phase) nearest to the top of the screen moves first.
The speed of the slowest unit determines the hero's movement on the adventure map.
Native Terrain
Units fighting on their native terrain get +1 speed.