Wu Wei
ursus senum severiorum and ex-Bisy Backson
True, also the US Civil war, might be the first "industrial war" but then wars of antiquity could be pretty darn devastating as well.Maybe "industrial warfare" might be a more appropriate term for warfare in more recent times. The World Wars were so horrific due to the kinds of machines and weapons they had, far more devastating than what people had seen in past wars in previous centuries.
I remember Herman Wouk's War and Remembrance had the line "Either war is finished, or we are."
Battle of Julu
The Qin commander was Zhang Han, while the Chu leader was Xiang Yu. The battle concluded with a decisive victory for the rebels over the larger Qin army. The battle marked the decline of Qin military power as the bulk of the Qin armies were destroyed in this battle. 200,000 killed in battle.
And after that would be the collateral damage in lives and property of civilians, perpetrated by the victors