Dubious Provenance

Causal weapons are a myth, an arms-dealer’s con trick. Their official mention in the Ley Accords was no more than a paranoid’s precaution, deliberate disinformation, or a warning to those who might become too attached to oracles and knight’s-move stratagems. The universe was block, that was known; no retroactive editing-out permitted. Their reality, therefore – that was on the same level as the Precursor fittlers, three-ended wormhole recipes, bootleg godseeds, pocket universes, negative-mass antimatter, treasure maps to the Amphigory fleet and volumetric claims to Sector Zero, the Absolute Center and Place of Creation, that any downport slash-trader stocked in abundance for the most gullible and rich marks.

So why, he wondered, did this benzene-sweating azayf look so terrified of the… half-melted-semi-helix-blob-thing on the table between them?

Trope-a-Day: Earth Shattering Kaboom

Earth Shattering Kaboom: The Ulijen Disaster.  If you’re going to build an experimental power plant that taps power from your sun using a wormhole, don’t build it on the planetary surface!

Also, relativistic kill vehicles and really big strangelet bombs, or even antimatter bombs; and in theory, some other esoterica like twist-pinch bombs and causal weapons.  All of which are utterly, utterly illegal to use (which doesn’t stop everyone with a sense of paranoia from maintaining a relativistic deterrent fleet, of course) under pain of serious obliteration.