Kensho Obayashi (大林 賢将, Ōbayashi Kenshō), born Kim Bǒn-u (Korean: 김번우; January 27, 1982), and formerly Shigemasa Kanaya (金谷 成格, Kanaya Shigemasa), is a Japanese bodybuilder, professional wrestler, and former boxer best known by his ring name Zeus (ゼウス, Zeusu). He is currently signed to Osaka Pro Wrestling, where he also serves as owner and company president. He is perhaps best known for his time in All Japan Pro Wrestling (AJPW), where he is a former AJPW Triple Crown Heavyweight Champion and a four-time World Tag Team Champion alongside Bodyguard as The Big Guns.

Obayashi began his career in Osaka Pro, where he is a former Osaka Pro Champion and three-time Osaka Tag Team Champion, winning the championship once with Gaina and twice with longtime rival-turned-partner Bodyguard. Outside of Osaka Pro and All Japan, he is a former NWA Intercontinental Tag Team Champion, NWA United National Heavyweight Champion and winner of the 2012 Furinkazan Tournament with James Raideen in the Zero1 promotion, and a former Ironman Heavymetalweight Champion in DDT Pro-Wrestling (DDT).

Obayashi is of Korean descent. His Korean name is Kim Bǒn-u (金 繁優, 김번우), but he used the tsūmei Shigemasa Kanaya (金谷 成格, Kanaya Shigemasa) until he legally changed his name to Kensho Obayashi when he was naturalized in 2011.

In the run up to the 2006 Tennozan Finals, a brief video hyped up the debut of a mysterious new wrestler. That man was revealed to be Zeus, who would make his first appearance at that show, first bending a frying pan in a show of strength and then aligning himself with Gaina & Condor, taking out the OPW Seikigun. Soon after joining forces, the group dubbed themselves "Bad Force". Nicknamed "God of Destroy", Zeus went undefeated for several months after his debut. He teamed up with Gaina to win the Osaka Pro Tag Title shortly afterwards, but they would lose them at Hurricane 2007 to Hideyoshi & Masamune in a three-way match also featuring Tsubasa and Flash Moon. Zeus started to break out as a singles wrestler in late 2007, reaching the Tennozan final but losing to the Osaka Pro Champion, Tigers Mask. Super Delfin then started to take an interest in Zeus, offering to teach him more about professional wrestling and give him further training. Despite the rest of Bad Force’s protests, Zeus accepted Delfin’s offer and eventually left the group. After Hurricane 2008, he started the rookie group Blood & Guts (B&G), recruiting Daisuke Harada, Tadasuke and eventually Atsushi Kotoge to join.

In 2008, Zeus started to appear in other promotions, most notably facing and later teaming with veteran Toshiaki Kawada in Hustle. It was in Hustle that he picked up a clean singles win over former IWGP Heavyweight Champion Bob Sapp. Zeus produced his own show in December and hinted at a major announcement at Hurricane 2009. After defeating the Bodyguard, Zeus announced that he was going to start training for a career in boxing and that he would be leaving the wrestling industry effective immediately.

After retiring from boxing, Obayashi announced his return to professional wrestling in July 2010. His in-ring return was delayed after he underwent further training and spent time to trying to build up body mass after losing a lot of weight for boxing. His official return to wrestling took place in November 2010 at Osaka Pro: Zeus Will Be Back, where he teamed with Daisuke Sekimoto to defeat Akebono and Don Fujii. Shortly after returning, Zeus re-ignited his old rivalry with the Bodyguard. The two traded wins back and forth for months, but eventually formed a tag team in early 2011 after Bodyguard was kicked out of the Joker stable, and Zeus saved him from an attack by the rest of Joker. Known collectively as the Big Guns, they would go on to hold the Osaka Pro Tag Title for a short time in early 2011. The Big Guns started to achieve major success in 2013, winning the Osaka Tag Festival and the Osaka Pro Wrestling Tag Team Championship for the second time later that year. In the 2013 Tennozan, Zeus and Bodyguard faced each other in the finals with Zeus coming out victorious. On March 1, 2014, it was announced that Osaka Pro would be folding due to financial difficulties. On April 20, all of its workers became freelancers. It was later announced that the promotion would continue under new management, but Zeus and Bodyguard eventually vacated their all of their championships, and on April 20 wrestled their last match in OPW, teaming with Quiet Storm in a losing effort against Billyken Kid, Bull Armor Takuya and Black Buffalo.

In October 2021, he announced that he had been appointed as the owner and president of Osaka Pro Wrestling. He became president on July 30, and on August 26, he received a share transfer from former owner Yuji Sakagami. However, he remained under contract with All Japan Pro Wrestling (AJPW) for the rest of the year.

Zeus debuted with Zero1 in 2011, taking part in the 2011 Fire Festival, finishing with 3 points and therefore not advancing to the final. In September, he teamed with Masato Tanaka to capture the NWA Intercontinental Tag Team Championship from Kohei Sato and Kamikaze. Zeus and Tanaka held the title for over a year, eventually losing them to Yusuke Obata and Shito Ueda in November 2012. Zeus and James Raideen participated in the 2012 Furinkazan tournament, defeating Ueda and Obata in the final on December 15. On February 3, 2013, Kohei Sato and Zeus received an opportunity at the vacated NWA Intercontinental Tag Team Championship, but lost to Zero64 (Akebono and Daisuke Sekimoto). On July 30, Zeus defeated Ikuto Hidaka to win the NWA United National Heavyweight Championship. Zeus held the championship for 6 months, losing it in January 2014 to Tama Williams in his first defense and last appearance in Zero1 to date.