Mbh 7.137.2a

“Sanjaya said, ‘Indeed, O king, Karna and Bhima, both endued with great prowess, continued in that battle to pour their arrowy showers like two rain-charged clouds. The arrows, winged with gold and whetted on stone and marked with Bhima’s name, approaching Karna, penetrated into his body, as if piercing into his very life. Similarly, Bhima also, in that battle was shrouded with the shafts of Karna in hundreds and thousands, resembling snakes of virulent poison. With their arrows, O king, falling on all sides, an agitation was produced among the troops resembling that of the very ocean. Many were the combatants, O chastiser of foes, in thy host that were deprived of life by arrows, resembling snakes of virulent poison shot from Bhima’s bow. Strewn with fallen elephants and steeds mixed with the bodies of men, the field of battle looked like one covered with trees broken by a tempest. Slaughtered in battle with the arrows from Bhima’s bow, thy warriors fled away, saying, “What is this?” Indeed, that host of the Sindhus, the Sauviras, and the Kauravas, afflicted with the impetuous shafts of both Karna and Bhima, was removed to a great distance. The remnant of those brave soldiers, with their steeds and elephants killed, leaving the vicinity of both Karna and Bhima, fled away in all directions. (And they cried out), “Verily, for the sake of the Parthas, the gods are stupefying us, since those arrows shot by both Bhima and Karna are slaying our forces.” Saying those words, these troops of thine afflicted with fear avoiding the range of (Karna’s and Bhima’s) arrows, stood at a distance for witnessing that combat. Then, on the field of battle there began to flow a terrible river enhancing the joy of the heroes and the fears of the timid. And it was caused by the blood of elephants and steeds and men.