In the additional reading of the Southern recension of Mahābhārata, there are some ślokas regarding the vālyalīlā (valyalila; childhood play) of Kṛṣṇa. In one of these verses, we get the name of Ariṣṭa. Assuming the form of a bull, he came to kill Kṛṣṇa. Kṛṣṇa slew him in order to to good to all the animal-world —
jaghāna tarasā kṛṣṇa paśūnā hitakāmāya.
According to Purāṇa(s), Ariṣṭa is a Demon commissioned by kaṃsa. In Bhāgavatapurāṇa (Bhagavatapurana), the destructive form of the bull called Ariṣṭa has been described. And from Kṛṣṇa’s own words, we come to know that this demon caused terror amongst the cattles and the shepherds. Kṛṣṇa broke off one of his horns, and killed him with that horn itself. Nārada(narada) gave the news of Ariṣṭa’s death to Kaṁsa (kamsa). According to Viṣṇupurāṇa (Vishnupurana), when Kṛṣṇa was engaged in Rāsakrīḍā (Rasakrida) with the Gopinī(s), the bull-demon Ariṣṭa attacked him. In Bhāgavatpurāṇa (Bhagavatapurana), too, after killing Ariṣṭa, Kṛṣṇa got reunited with the Gopinī(s). According to Harivaṃśa, the time of Ariṣṭa’s attack was ardhapradoṣa (ardhapradosha; more than evening), that is, almost one and a half hour has passed after the onset of evening, and Kṛṣṇa was still with the Gopinī(s) — pradoṣārdhe kadācittu kṛṣṇe ratiparāyaṇe. 

The process of slaying Ariṣṭa is more or less the same in all the Purāṇa(s). In most of the readings of Mahābhārata (Mahabharata), there is no mention of Ariṣṭa, but in Sabhāparva (Sabhaparva), while abusing Kṛṣṇa, Śiśupāla (Sisupala) casually mentions that Kṛṣṇa killed the Aśvāsura (Aswasura; the horse-demon) and the Vṛṣabhāsura (Vrishabhasura; the bull-demon).
tau vāsvavṛṣabhau bhīṣma yau na yuddhaviśāradau.