This is about the battle between Baba Banda Singh Bahadur and Mughals, when Banda captured many territories in Panjab , mughals put their full effort on getting him. Now Baba Banda and many soldiers were held up in a fort that was surrounded by mughals , and it turned out many Sikh sects had abandoned him because they didn't care for his leadership over khalsa and also that one of Guru's Gobind's wife was staunchly against him , which led to a division in Sikhs . Now this only gave an edge to the Mughals. Banda and his men were captured , all gained territory was lost, this led a period of darkness where Sikhs were fractured and mini halocausts were happening every other yr . Had Baba Banda received cavalry and escaped for another day, he could've united the Sikh raj well before Maharaja Ranjit Singh.