The UAC/5 and Endo-Steel existed in the Star League, so I don't think there'd necessarily need to be prototype versions.
...Unless of course the UACs we have now turn out to be the prototypes, in which case I would be very happy.
Yes but it became LosTech, so they had to rediscover the tech which means they'd have to make prototypes again.
Do we have rules for any of the prototypes of the advanced Star League tech that went extinct?
On a side note, the fluff seems to indicate the freezers on the Super Griffin are not regular DHS, but the old caustic coolant type that only takes up 1 critical (Marauder has them too), but the record sheet lists regular DHS, what gives?
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XTRO:Sucession Wars 1 has a fighter, no large craft.
Warships were still extinct at that point anyways. If we want prototype warships i'd think they would be in an XTRO:Clan Invasion.