The zergspire is based on the towering spires of the mantis screamers, although altered to be sustained with creep. It holds the genetic code of the mutalisk.[1] The muscle stalks that make up its core section are flexible, and bend in strong winds. It can be considered the zerg equivalent of an aerospace complex. It retains vestigial air sacs, which were used by the mantis screamers as nests.[2]
The spire produces the genetic code that allows larvae to morph into mutalisks or split into pairs of scourge. It is capable of mutating into a greater spire after a hive has been developed, enabling the hive cluster to produce guardians and devourers.[1]
During the StarCraft alpha and beta, the spire possessed a different appearance from their final version which had its model borrowed from the scoria, a canceled zerg structure.[4]
The spire is usable by Kerrigan and Abathur in Co-op Missions. Both allow mutalisks to be spawned, and can be upgraded into a greater spire. Both commanders unlock additional upgrades upon reaching level 11.
100 Mastery: -2 per Expeditious Evolutions mastery point. Down to a minimum 40 100 Mastery: -2 per Expeditious Evolutions mastery point. Down to a minimum 40 160 Mastery: -3.2 per Expeditious Evolutions mastery point. Down to a minimum 64
Level 2
Cost
175 Mastery: -3.5 per Expeditious Evolutions mastery point. Down to a minimum 70 175 Mastery: -3.5 per Expeditious Evolutions mastery point. Down to a minimum 70 190 Mastery: -3.8 per Expeditious Evolutions mastery point. Down to a minimum 76
250 Mastery: -5 per Expeditious Evolutions mastery point. Down to a minimum 100 250 Mastery: -5 per Expeditious Evolutions mastery point. Down to a minimum 100 220 Mastery: -4.4 per Expeditious Evolutions mastery point. Down to a minimum 88
100 Mastery: -2 per Expeditious Evolutions mastery point. Down to a minimum 40 100 Mastery: -2 per Expeditious Evolutions mastery point. Down to a minimum 40 160 Mastery: -3.2 per Expeditious Evolutions mastery point. Down to a minimum 64
Level 2
Cost
175 Mastery: -3.5 per Expeditious Evolutions mastery point. Down to a minimum 70 175 Mastery: -3.5 per Expeditious Evolutions mastery point. Down to a minimum 70 190 Mastery: -3.8 per Expeditious Evolutions mastery point. Down to a minimum 76
250 Mastery: -5 per Expeditious Evolutions mastery point. Down to a minimum 100 250 Mastery: -5 per Expeditious Evolutions mastery point. Down to a minimum 100 220 Mastery: -4.4 per Expeditious Evolutions mastery point. Down to a minimum 88
150 Mastery: -3 per Expeditious Evolutions mastery point. Down to a minimum 60 150 Mastery: -3 per Expeditious Evolutions mastery point. Down to a minimum 60 60 Mastery: -1.2 per Expeditious Evolutions mastery point. Down to a minimum 24
150 Mastery: -3 per Expeditious Evolutions mastery point. Down to a minimum 60 150 Mastery: -3 per Expeditious Evolutions mastery point. Down to a minimum 60 90 Mastery: -1.8 per Expeditious Evolutions mastery point. Down to a minimum 36
200 Mastery: -4 per Expeditious Evolutions mastery point. Down to a minimum 80 200 Mastery: -4 per Expeditious Evolutions mastery point. Down to a minimum 80 120 Mastery: -2.4 per Expeditious Evolutions mastery point. Down to a minimum 48
150 Mastery: -3 per Expeditious Evolutions mastery point. Down to a minimum 60 150 Mastery: -3 per Expeditious Evolutions mastery point. Down to a minimum 60 60 Mastery: -1.2 per Expeditious Evolutions mastery point. Down to a minimum 24
The spire was a simple update of the original game's sprite artwork. The challenging aspect of creating the spire in 3D was conveying the height of the building. StarCraft II has height limitations for building models, especially for multiplayer artwork due to the altitude flying units move at. Buildings exceeding certain heights either require air pathing blockers so flying units don't clip through them, or height adjustments so they're lowered under the flight elevation. Air pathing blockers are not an option for multiplayer art, so the spire was lowered for the sake of functionality. Another consideration was making this building somewhat humble so the presence of a greater spire would be more significant.[5]
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![[1]](http://home.planet.nl/%7Eaggel005/alphabeta/beta/beta56.jpg){kind=link}