Infinity Missile

Probably the most crazy archeotech (and missile weapon) in the world. Infinity Missile is pretty much a simple missile, the size of shipkiller but of complicated internal structure. It's internal battery can store completely crazy ammount of power (the entire Infinity Missile launchers are pretty much additional power generators and loading station to power it up prior to launch), though it makes its nuclear warheads slightly smaller and limits their explosive power to about 13 megatones.
What makes it one of the most dangerous (and rarest) weapons in the Galaxy is that the missiles reproduce midflight. And do it fast, with the exact speed depending on the ammount of power loaded unto it before being launched. Despite the first Infinity Missile being found two centuries ago, there is no scientifical theories explaining the exponential growth of the Infinity Missiles. One is launched, but soon there are 2... 4... 8... 16... 32... 64... and so on. The longer they go before reaching the target, the more of them will be there (though they seem to run out of power or just disappear when one attempts to fire them against another star system).
The biggest Infinity Missile salvo to date was composed of 4194304 missiles and was enough to instantly wipe out one of the biggest fleet of the pre-Virus automata that threatened to wipe out all life in the Galaxy. There are insanely rare weapon - probably the rarest type of archeotech weaponry - but even a single Infinity Missile being found can topple the regional balance of power.