Emblems are items that increase the stats of your Hero, and even more if you have the right Hero equipped.

There are five emblems, one for each of the Mega Factions. Terran, Beast, Mech, Mercenary and Ancient. You'll have a slot in your loadout to equip an emblem, and which one you equip should depend on which Hero you're using.

Emblems will give a stat boost even if you are using a Hero that is not of the faction of the emblem. However, if you are using a Hero that is of that faction, you will get an additional stat boost.