Mbh 6.110.3b

Thus addressed by him, O king, thy sire Devavrata, the son of Santanu, reflecting for a moment and settling what he should do, said these words unto thy son, comforting him (therewith), ‘O Duryodhana, listen calmly to what I say, O king. O thou of great might, formerly I vowed before thee that slaying every day ten thousand high-souled Kshatriyas, I would come back from the battle. I have fulfilled that vow, O bull of Bharata’s race! O thou of great might, today I will achieve even a great feat. Today I will either sleep myself being slain, or, I will slay the Pandavas. O tiger among men, I will today free myself from the debt I owe thee,--the debt, O king, arising out of the food, thou gavest me,--by casting away my life at the head of thy army.’ Having said these words, O chief of the Bharatas, that invincible warrior, scattering his shafts among the Kshatriyas, attacked the Pandava host. And the Pandavas then, O bull of Bharata’s race, began to resist the son of Ganga staying in the midst of his forces and excited with wrath like a snake of virulent poison. Indeed, O king, on that tenth day of the battle, Bhishma, displaying his might, slew, O son of Kuru’s race, hundreds of thousands. And he drained the energies of those royal and mighty car-warriors that were the foremost among the Panchalas, like the Sun sucking up the moisture (of the earth) with his rays. Having slain ten thousand elephants of great activity and ten thousand steeds also, O king, along with their riders, and full two hundred thousands of foot-soldiers, that best of men, viz., Bhishma, shone resplendent in battle like a fire without a curl of smoke. And no one amongst the Pandavas was capable of even looking at him who then resembled the burning Sun staying in the northern solstice. The Pandavas, however, though afflicted in battle by that great bowman, still rushed, accompanied by the mighty car-warriors of the Srinjayas, for slaughtering him.