"Heavy barrel version of the Stormer that hurls a stream of mass driver rounds that do heavy damage."
Heavy Stormers unlock the weapon of the same name, Heavy Stormers(weapon). As the smaller Stormers are ten Gauss Cannons in the same barrel, Heavy Stormers are ten Mass Drivers in the same barrel with the important distinction that they have the Gauss Cannon's 80% ricochet resistance instead of the Mass Driver's 100%. This is the end of the tech path containing large Ballistic Weapons which fire quickly. While Stormers do have a potential use-case, Heavy Stormers are eclipsed by Heavy Drivers in all respects and can therefore always be skipped.

Heavy Stormers can cost up to 97,500 or as little as 32,500 research points to unlock, depending on luck.

Root Technology
And/Or Technology Research Cost Chance to Unlock Heavy Stormers
Hiver Human Liir Morrigi Tarka Zuul
And Stormers 25,000 90 80 50 40 85 90
Fission 0 0 0 0 0 0 0
Total Chance to Unlock Heavy Stormers 89.1 76.8 37.5 25.6 83.0875 89.1

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