Game Usage
 Zerg vs Terran
Fully upgraded Ultralisks are the most feared unit by Terrans, as they will have 6 armor. A fully upgraded Marine will only do 3 damage.
 Zerg vs Protoss
Ultralisks with Zerglings is a deadly combination vs Protoss, especially with Defiler support.
 Zerg vs Zerg
Since Zerg vs Zerg matches are determined by air battles, Ultralisks are never used.