Russia launched a massive attack on Ukraine overnight into Saturday with hundreds of drones, killing at least one person, part of a stepped-up bombing campaign that has dashed hopes for a breakthrough in efforts to end the more than 3-year-old war.

Men and equipment being hunted down along Ukraine's long, contested front lines. Everything filmed, logged and counted. And now put to use too, as the Ukrainian military tries to extract every advantage it can against its much more powerful opponent.

They're cheap, they're deadly and they're among the main reasons Ukraine believes it can hold out against advancing Russian forces this year and even beyond, according to a dozen Ukrainian commanders,