Son of Kritavirya, King of Haihaya. He had a thousand arms, that’s why he is also called Sahasrabahu Arjuna.
Kartavirya Arjunas army stole the wish fulfilling cow am sage Jamadagni. Jamadagni’s son, Parashurama, destroyed Kartavirya Arjuna’s army and brought the cow back. Kartavirya Arjuna’s sons killed Jamadagni. Parashurama vowed to eradicate the warrior caste (kshatriyas).
Read about Kartavirya Arjuna here