Target may be able to duck in time and you'd only get one attack per drone. Maybe a gyrojet explosive tip munition with poison coating for the shrapnel, where the firing drone could time the tip detonation by tracking the projectile in real time after launch. That would be light enough to provide several shots or for multiple targets. With infrared target the jugular. Highly inconvenient to defend against with armor and the projectile will be incoming fast enough such that there's no opportunity to evade, assuming it can get in range quietly. There's a huge market for this. From nation states to divorcing couples