Bhai Bachittar Singh ji
Guru Gobind Singh Ji and a small number of Sikhs were defending their position in Lohgarh fort of Anandpur during The Second Battle of Anandpur, which was under attack by numerically far superior forces under the rule of the Mughal Emperor Aurangzeb and the Hindu rulers of the Hill States. Despite superior numbers, the besieging forces were unable to penetrate the heavily-defended fort. They brought forth an armoured, drunken elephant to batter the gates open. Bhai Bachittar Singh was tasked with stopping the elephant, armed with a Nagni Barcha, 'Serpentine' Spear, a type of spear that has more piercing potential. As the elephant approached the gate, Bachittar Singh, sallied forth on horseback and made a powerful thrust with his spear piercing the elephant's armour plate and injuring the animal in the forehead. The wounded elephant ran back creating havoc and great damage in the enemy ranks. As a result of Bachittar Singh's bold action, the Sikhs gained an upper hand in this conflict. (Wiki, fixed spelling errors and clarified a bit)