Maudgalyāyana (Sk.) or Moggallāna(Pl.), also known as Mahāmaudgalyāyana or Mahāmoggallāna. He is a top master of supernatural powers. Maudgalyayana and Śāriputra were once disciples of Sañjaya Belaṭṭhaputta, the skeptic, but they became disciples of the Buddha. In Chinese Buddhism, the Mass that Maudgalyayana held to save his mother who had gone to the Hungry Ghost realm (one of the Six realms) is the foundation of ullambana (Ghost Festival).
Mahākāśyapa (Sk.) or Mahākassapa (Pl.). He was a top master of ascetic training. After the death of Shakyamuni Buddha, he assumes the leadership of the sangha, compiled the Buddha's sayings (suttas) with 500 other disciples (First Buddhist councils), and became the first man who preached the Buddha's teachings directly.
Kātyāyana or Mahākātyāyana (Sk.) or Mahākaccāna (Pl.). He understood Shakyamuni Buddha's lecture the best. Although he had only five master in the rural areas, he was permitted to learn Vinaya by the Buddha.
Anuruddha (Pl.) or Aniruddha (Sk.) was a top master of clairvoyance and the practice of the four foundations of mindfulness (satipatthana). Aniruddha was a cousin of Shakyamuni Buddha. He and Ananda became monks at the same time.
Upāli (Sk. & Pl.) was a top master of Vinaya. He was born in the Shudra class and worked as a barber. Buddha had denied the class system, he ranked his disciples according to the order in which they joined. So Upali was ranked ahead of the ex-princes. In the First Buddhist council, the Vinaya was compiled based on his memory.
Rāhula (Sk. & Pl.) was the only son of the Buddha (when he was still Prince Siddartha) and his wife Princess Pṛthī. He was a scrupulous, strict and shrewd person. When the Buddha went to his hometown, he became the first Sāmanera (novice monk).
Ānanda (Sk. & Pl.) listened to the Buddha's teachings the most among the disciples. He was a cousin of the Buddha. Ananda means great delight. After he became a monk, he took care of the Buddha for 25 years, until the Buddha died. In the First Buddhist council, the suttas/sutras were compiled based on his memory. He lived to 120 years old.