I know that he was a Kaurava.
I read that he tried to stop Draupadi's Cheerharan. Is there truth behind this?
Also, did he play any other role in the Mahabharata?
Vikarna was one of the 101 Kauravs, the son of Dhritarastra. His order of birth was as:
The Mahabharata, Book 1: Adi Parva: Sambhava Parva: Section CXVII
"Janamejaya said, 'Please recite the names of Dhritarashtra's sons according to the order of their birth.' "Vaisampayana said, 'Their names, O king, according to the order of birth, are Duryodhana, Yuyutsu, Duhsasana, Duhsaha, Duhsala, Jalasandha, Sama, Saha, Vinda and Anuvinda, Durdharsha, Suvahu, Dushpradharshana, Durmarshana and Durmukha, Dushkarna, and Karna; Vivinsati and Vikarna, Sala, Satwa, Sulochana, Chitra and Upachitra, Chitraksha, Charuchitra, Sarasana, Durmada and Durvigaha, Vivitsu, Vikatanana; Urnanabha and Sunabha, then Nandaka and Upanandaka; Chitravana, Chitravarman, Suvarman, Durvimochana; Ayovahu, Mahavahu, Chitranga, Chitrakundala, Bhimavega, Bhimavala, Balaki, Balavardhana, Ugrayudha; Bhima, Karna, Kanakaya, Dridhayudha, Dridhavarman, Dridhakshatra, Somakitri, Anudara; Dridhasandha, Jarasandha, Satyasandha, Sada, Suvak, Ugrasravas, Ugrasena, Senani, Dushparajaya, Aparajita, Kundasayin, Visalaksha, Duradhara; Dridhahasta, Suhasta, Vatavega, and Suvarchas; Adityaketu, Vahvashin, Nagadatta, Agrayayin; Kavachin, Krathana, Kunda, Kundadhara, Dhanurdhara; the heroes, Ugra and Bhimaratha, Viravahu, Alolupa; Abhaya, and Raudrakarman, and Dridharatha; Anadhrishya, Kundabhedin, Viravi, Dhirghalochana Pramatha, and Pramathi and the powerful Dhirgharoma; Dirghavahu, Mahavahu, Vyudhoru, Kanakadhvaja; Kundasi and Virajas. Besides these hundred sons, there was a daughter named Duhsala. All were heroes and Atirathas, and were well-skilled in warfare. All were learned in the Vedas, and all kinds of weapons. And, O, king, worthy wives were in time selected for all of them by Dhritarashtra after proper examination. And king Dhritarashtra, O monarch, also bestowed Duhsala, in proper time and with proper rites, upon Jayadratha (the king of Sindhu).'
He tried to stop disrobing of Draupadi as:
The Mahabharata, Book 2: Sabha Parva: Sisupala-badha Parva: Section LXVI
'Bhima said,--'If I had not known, O Dhananjaya, that the king had acted according to Kshatriya usage, then I would have, taking his hands together by sheer force, burnt them in a blazing fire." Vaisampayana continued,--"Beholding the Pandavas thus distressed and the princess of Panchala also thus afflicted, Vikarna the son of Dhritarashtra said--'Ye kings, answer ye the question that hath been asked by Yajnaseni. If we do not judge a matter referred to us, all of us will assuredly have to go to hell without delay. How is that Bhishma and Dhritarashtra, both of whom are the oldest of the Kurus, as also the high-souled Vidura, do not say anything! The son of Bharadwaja who is the preceptor of us, as also Kripa, is here. Why do not these best of regenerate ones answer the question? Let also those other kings
assembled here from all directions answer according to their judgment this question, leaving aside all motives of gain and anger. Ye kings, answer ye the question that hath been asked by this blessed daughter of king Drupada, and declare after reflection on which side each of ye is.' Thus did Vikarna repeatedly appeal to those that were in that assembly. But those kings answered him not one word, good or ill. And Vikarna having repeatedly appealed to all the kings began to rub his hands and sigh like a snake. And at last the prince said--'Ye kings of the earth, ye Kauravas, whether ye answer this question or not, I will say what I regard as just and proper. Ye foremost of men, it hath been said that hunting, drinking, gambling, and too much enjoyment of women, are the four vices of kings. The man, that is addicted to these, liveth forsaking virtue. And people do not regard the acts done by a person who is thus improperly engaged, as of any authority. This son of Pandu, while deeply engaged in one of these vicious acts, urged thereto by deceitful gamblers, made Draupadi a stake. The innocent Draupadi is, besides, the common wife of all the sons of Pandu. And the king, having first lost himself offered her as a stake. And Suvala himself desirous of a stake, indeed prevailed upon the king to stake this Krishna. Reflecting upon all these circumstances, I regard Draupadi as not won." "Hearing these words, a loud uproar rose from among those present in that assembly. And they all applauded Vikarna and censured the son of Suvala. And at that sound, the son of Radha, deprived of his senses by anger, waving his well-shaped arms, said these words,--'O Vikarna, many opposite and inconsistent conditions are noticeable in this assembly. Like fire produced from a faggot, consuming the faggot itself, this thy ire will consume thee. These personages here, though urged by Krishna, have not uttered a word. They all regard the daughter of Drupada to have been properly won. Thou alone, O son of Dhritarashtra in consequence of thy immature years, art bursting with wrath, for though but a boy thou speakest in the assembly as if thou wert old. O younger brother of Duryodhana, thou dost not know what morality truly is, for thou sayest like a fool that this Krishna who hath been (justly) won as not won at all. O son of Dhritarashtra, how dost thou regard Krishna as not won, when the eldest of the Pandavas before this assembly staked all his possessions? O bull of the Bharata race, Draupadi is included in all the possessions (of Yudhishthira). Therefore, why regardest thou Krishna who hath been justly won as not won? Draupadi had been mentioned (by Suvala) and approved of as a stake by the Pandavas. For what reason then dost thou yet regard her as not won? Or, if thou thinkest that bringing her hither attired in a single piece of cloth, is an action of impropriety, listen to certain excellent reasons I will give. O son of the Kuru race, the gods have ordained only one husband for one woman. This Draupadi, however, hath many husbands. Therefore, certain it is that she is an unchaste woman. To bring her, therefore, into this assembly attired though she be in one piece of cloth--even to uncover her is not at all an act that may cause surprise. Whatever wealth the Pandavas had--she herself and these Pandavas themselves,--have all been justly won by the son of Suvala. O Dussasana, this Vikarna speaking words of (apparent) wisdom is but a boy. Take off the robes of the Pandavas. as also the attire of Draupadi. Hearing these words the Pandavas, O Bharata, took of their upper garments and throwing them down sat in that assembly. Then Dussasana, O king, forcibly seizing Draupadi's attire before the eyes of all, began to drag it off her person."
He also fought with Arjuna in Virata Goharan Parva:
The Mahabharata, Book 4: Virata Parva: Go-harana Parva: Section LIV
Then, when the battle began to rage furiously, the Kuru hero, Vikarna, mounted on his chariot, approached that foremost of chariot-warriors, Partha, the younger brother of Bhima,--showering upon him terrible shafts thick and long. Then cutting Vikarna's bow furnished with a tough string and horns overlaid with gold, Arjuna cut off his flagstaff. And Vikarna, beholding his flagstaff cut off, speedily took to flight. And after Vikarna's flight, Satruntapa, unable to repress his ire, began to afflict Partha, that obstructer of foes and achiever of super-human feats, by means of a perfect shower of arrows. And drowned, as it were, in the midst of the Kuru-array, Arjuna, pierced by that mighty chariot-warrior,--king Satruntapa--pierced the latter in return with five and then slew his chariot-driver with ten shafts, and pierced by that bull of the Bharata race with an arrow capable of cleaving the thickest coat of mail, Satruntapa fell dead on the field of battle, like a tree from a mountain- top torn up by the wind....
He was one of the major warrior in the side of Kaurav as Duryodhan in Bhagvad Gita 1.8 mentions his name:
भवान् भीष्मश्च कर्णश्च कृपश्च समितिञ्जय: । अश्वत्थामा विकर्णश्च सौमदत्तिस्तथैव च ।।
There are personalities like you, Bhishma, Karna, Kripa, Asvatthama, Vikarna and the son of Somadatta called Bhurisrava, who are always victorious in battle.
He was slained by Bhima in the battle in Jayadrath Vadh Parva and he laments for Vikarnas death as:
The Mahabharata, Book 7: Drona Parva: Jayadratha-Vadha Parva: Section CXXXVI The seven sons of thine that were thus slain were Satrunjaya, and Satrusaha, and Chitra, and Chitrayudha, and Dridha, and Chitrasena and Vikarna. Amongst all thy sons thus slain, Vrikodara, the son of Pandu, grieved bitterly from sorrow for Vikarna who was dear to him. And Bhima said, 'Even thus was the vow made by me, viz., that all of you should be slain by me in battle. It is for that, O Vikarna, that thou hast been slain. My vow hath been accomplished. O hero, thou camest to battle, bearing in mind the duties of a Kshatriya. Thou wert ever engaged in our good, and especially in that of the king (our eldest brother). It is scarcely proper, therefore, for me to grieve for thy illustrious self.'