In Jack Vance’s The Dirdir there was an explosive called “battarache”. Adam Reith’s handgun fired exploding needles. In The Face Lens Larque employed a mining or quarrying explosive called DEXAX in industrial quantities for an imaginative project. There was no particular sign that the explosives were extraordinarily powerful, though you need to get a lot of bang into a small space to make an exploding needle worthwhile.
ForeSight settled on a TL7* explosive called “DEXAX” that was “dangerously unstable” and as dangerous to use as dynamite, but with sixty times the destructive power of TNT. At TL8† it gave us “Plasdex”, developed from DEXAX, and as safe to use as plastique, but only 24 times as destructive as TNT. And for TL9 it offered “Durex”, as safe as plastique or plasdex, but fifty times as bang-o-genic as TNT (I didn’t accept; Flat Black is TL8). At TL8 the “DEXAX needler” and “DEXAX needle rifle” were the civilian pistol and rifle of choice, player characters not caring for spectacular side-effects of laser weapons. I presumed that they were firing something like plasdex, regardless of the name.
DEXAX and its derivatives became part of the texture of Flat Black, like its characteristic weapons and armour, like foam grenades. But I’ve cut ForeSight-isms before, such as the bionic modifications from ForeScene, which used to be standard. I’m prepared to axe DEXAX if it doesn’t carry its own weight in terms of the suspended disbelief.
So: how does DEXAX compare to stuff in GURPS? HEDM rocket fuel has eleven times the energy density of chemical rocket fuel, and is marked TL9, not TL9^. Antimatter-catalysed hydrogen (actually an annihilation fuel, not AM-catalysed fusion fuel) has 144 times the energy density of chemical rocket fuel and is not marked “^”. But when I suggest that DEXAX might be a rocket-fuel derivative having positrons “chelated in molecular Penning traps” GURPS players get very worried about the gamma-rays.
Ought I to keep DEXAX, plasdex, and the DEXAX needle weapons?
* Using the ForeSight scale of tech levels TL7 is the range in which laser smallarms and armoured exoskeletons become practical, the next stage after the Fusion Age. It is an age in which FTL travel is possible only with co-operation at the destination. I map it to GURPS TL9(advanced) and TL10(delayed)
† Using the ForeSight scale of tech levels TL8 is the range in which we get aircars, smartphones, and convenient FTL travel. I map it to GURPS TL10(standard) and TL10(advanced)