It was the Primary Weapon of Lord Krishna and he used it many times against powerful foes. One of the notable feats with this weapon is when he used it to cut off the thousands hands of Banasura:
With great force Gadadhara, worked up with ire, took up that wonderful discus, effulgent like the sun, at the discharge of which, all the worlds, mobile and immobile, become unconscious and flesh-eating creatures find great pleasure, discharged it and cut off Vana’s arms. When discharged by Shridhara, parmeating the universe, that firmament-like discus so moved about in the battle-field that no body could see its true form. Gradually cutting off Vana’s thousand arms and making him the owner of only two the Sudarshana discus returned into Krishna’s hands.
Narayanastra
He used this weapon to counter the Pashupatastra of Lord Shiva in Banasura Battle:
Lord Kṛṣṇa counteracted a brahmāstra with another brahmāstra, a wind weapon with a mountain weapon, a fire weapon with a rain weapon, and Lord Śiva’s personal pāśupatāstra weapon with His own personal weapon, the nārāyaṇāstra.
Vaishnavastra
In Shoniputra battle, He terrified and defeated Bhutas, Yakshas and Asuras using this weapon:
Having thus counteracted those four weapons with his four arrows Madhava discharged his Vaishnava weapon like unto Antaka (the destroyer) with his mouth wide open. When the Vaishnava weapon was discharged all the Bhutas, Yakshas and Asuras of Vana’s host, unconscious and stricken with fear, fled on all sides. Then beholding his army abounding in Pramathas thus routed the great Asura Vana speedily ran towards the battle-field.
Saranga Bow
One of the 3 great bows mentioned in Mahabharat previously owned by Vishnu himself:
There were three celestial bows owned by the denizens of heaven, viz., Gandiva owned by Varuna, the bow called Vijaya owned by Indra, and that other celestial bow of great energy said to have been owned by Vishnu. This last (Sarnga), capable of striking fear into the hearts of hostile warriors, was held by Krishna.
Kaumodaki Mace
He used this mace to kill Dantavakra:
Although hit by Dantavakra’s club, Lord Kṛṣṇa, the deliverer of the Yadus, did not budge from His place on the battlefield. Rather, with His massive Kaumodakī club the Lord struck Dantavakra in the middle of his chest. His heart shattered by the club’s blow, Dantavakra vomited blood and fell lifeless to the ground, his hair disheveled and his arms and legs sprawling
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