A duel begins and ends with one stroke. So it is said.

With tactical prolepsis, this is even more true than it once was.

I stared at my opponent without seeing him; in the view of proleptics, there are no objects, only clouds of probability and possibility. The quantum computer in my head purred to itself, whispering tactical analysis engrams into my undermind and running massively-parallel anticipatory simulations.

The target was a blob of probable solidity, fuzzy with microcausal jitter. Bifurcating arcs of destiny writhed in secondary visual fields, ignored to concentrate on the glittering blurs of near-term possibility, threatening to actualize at any moment.

One second passed. Two.

A third, and then a probability spike, one possible future hardening towards actualization. I took one step to the left, my cannon rising in my hand. Distantly, I felt the tremor as the flechette left the barrel; something whipped past my ear, ruffling my hair with the wind of its passage; and then he was falling, helmet shattered and venting rapidly-condensing gas into the void.

One stroke.