Kumbhakarn was a rakshasa and brother of Ravan. Despite of his monstrous size and great hunger, he was somewhat described of having a good character, though he killed and ate many sages just to show his power.
He was considered so pious, intelligent and brave that Indra was jealous of him. Along with his brothers, Ravan and Vibhishana, he performed a major yajna andpenance for Lord Brahma. When the time came for asking a boon (blessing) from Brahma, his tongue was tied by goddess Saraswati . So instead of asking “Indraasana” (seat of Indra), he asked for “Nidraasana” (bed for sleeping). His request was granted. But his brother Ravan asked Brahma to undo this boon as it was in reality a curse. In another version of the story Kumbhakarn did another austerity to ask Brahma to take his boon back and make him alert always. Thus Brahma decided that Kumbhakarn would sleep for six months at a stretch and remain awake for another six consecutive months. So when Kumbhakarn woke up from six months sleep, when he ate everything in the vicinity, including humans.
During the war, Ravan went into battle and was humiliated by Ram and his army. He decided he needed the help of his brother Kumbhakarn, who was awakened with great difficulty. When he was informed of the circumstances of Ravan’s war with Ram, he tried to convince Ravan that what he was doing was wrong. Some sources do not imply that he said any such thing to Ravan, rather, they mention that he sided with his brother wholeheartedly. However, he chose to fight in the battle due to his loyalty to his brother. After becoming drunk, Kumbhakarn went into battle. He devastated Ram’s army, injured Hanuman, and knocked Sugriv unconscious and took him as a prisoner . Therefore Rama took the charge of the battle by himself. Kumbhakarn had magical power and he was adept with many illusive forms to confuse the enemy. It was difficult to hit Kumbhakarn`s true body as many Kumbhakarn appeared in front and all the missiles and arrow missed him. The battle continued for quite a long time. Finally Rama attacked Kumbhakarn with his most powerful arrow strengthened with deadly divine missile. When this missile hit Kumbhakarn his life came to an end. When Ravan heard of his brother’s death, he fainted and proclaimed that he was doomed.
Kumbhakarn had two sons, Kumbha and Nikumbha, who too fought in the war against Ram and were killed.
Kumbhakarn was certainly one of the most interesting characters in the Ramyan epic. Kumbhakarn was able to realize the mistakes and wrong-doings of Ravan, even trying to intervene and moderate at certain times, he was unable to openly oppose him, feeling bound by his warrior ethics. Fighting on what he knew was the wrong side, he was ultimately killed in combat. When he was finally defeated, he annihilated in Lord Ram and got salvation.