Early years: 2005–11 The team was founded as the
Oita HeatDevils in 2005 and were one of six founding members of the
bj league, a professional league set up in competition to the
Japan Basketball League operated by the
Japan Basketball Association. Their first league game was on 5 October 2005, which they won 100–95 against
Osaka Evessa. After losing to Osaka in their second match the following day, Oita hosted their first home game a week later against the
Sendai 89ers at the
Beppu Beacon Plaza. They lost both matches in the series though, and their losing streak increased to six until they won the second game of a return series in Sendai on 3 December. After that they won just two of their next twelve matches for a 4–16 win–loss record at the mid-point of the season. Oita improved in the second half of the season and managed a six-game winning streak at one stage. They finished in fifth place with a 15–25 win–loss record, three games behind fourth-placed Sendai. They lost their semi-final against the top-placed and eventual champions
Osaka Evessa 69–63, before recovering the next day to defeat
Niigata Albirex BB 92–70 in the playoff for third. To increase their popularity in the wider region, the team played half of their home games in Beppu and two matches each in
Hita,
Oita and
Usa cities in Oita Prefecture as well as
Buzen and
Fukuoka cities in
Fukuoka Prefecture. Coach
Dai Oketani left the club at the end of the season. The following year the team hired former
NBA player
Brian Rowsom to coach the club. He led the team to a 25–27 record, finishing 5th in the Western Conference, four games outside of the playoffs behind the
Shiga Lakestars. In the middle of April Oita was just one game behind Shiga, but a poor finish to the season once again hurt the team, losing four of their final six matches while Shiga won five over the same period. However, three of the team's four American players (
Taj Finger,
Rolando Howell and
Cyrus Tate) broke their contracts and left the country in the week after the earthquake and the team subsequently fired coach
L. J. Hepp for failing to convince the players to remain in Japan.
Suzuki years: 2011–15 The team's star player Yukinori Suzuki, who had been with the club since its inception and appeared in three All-Star matches, retired at the end of the 2010–2011 at the age of 34 in order to take over as the club's head coach. Oita started the 2011–2012 season poorly, winning just five of their 24 games before the All-Star break. But they finished the season strongly, winning 14 of their last 17 games, including a 7-game streak in March and the final 5 games of the season, finishing 7th in the 10-team conference with a 23–29 record. to sit second in the Western Conference standings. However during this time Tomohiro Hashimoto, the president of Oita Heat, the company that owned the team, reported to the league that negotiations with a planned season sponsor had not gone well. On 22 November Hashimoto requested a 25 million yen bailout from the league's assistance fund and the league, anticipating the company's demise, established an incorporated association named Temporary Game Operation (TGO). A week later the league determined that Hashimoto's request was without the agreement of the company's shareholders and refused the request. On 3 December Oita Heat requested withdrawal from the league and control of the team was transferred to TGO. In the second half of the season TGO secured the services of new foreign players and the team managed a 12–14 record to finish in 8th place. In May 2013 ownership of the team was transferred to the corporation. Under new corporate ownership for 2013–14, the team was unable to secure a main sponsor prior to the start of the season. The team planned to host a two-game series against the expansion team
Bambitious Nara on 25 and 26 October at
Ōita Bank Dome, a 40,000-capacity stadium with a retractable roof. This match was to be the first game in Japanese basketball history played in an outdoor stadium. Despite the various setbacks, Oita started the season strongly and were tied for second place in the Western Conference after 16 games. As the season wore on, the team started to suffer several losing streaks, and slid down the standings to finish in eighth position with a 20–32 record, four games outside the top six. For the 2014–15 the league's playoff bracket was further expanded so that the top 8 teams of each conference qualified for the finals. On 16 April 2015, with the HeatDevils in 7th place and guaranteed their first playoff appearance in eight years, the league announced the withdrawal of Oita's operating company Basukede from the league due to their worsening financial position, after reporting losses of 120 million yen over their two years of ownership. On 20 April Basukede concluded an agreement for transfer of ownership of the club to KBC Total Services, They met the reigning champion
Ryukyu Golden Kings in the first round of the playoffs and recorded a surprising 74–67 win in Game 1 of the three-game series after trailing 21–9 at quarter time. Ryukyu recovered the next day to win Game 2 92–68, as well as the 10-minute tiebreaker match 23–18 that was played immediately after Game 2. Suzuki left the club at the end of the season, having recorded an 82–126 (39.4%) win–loss record during his four years as coach of the team. In the same press release, the team announced their intention to seek public proposals for a new name for the team for the 2016–17 season. The following month an official request for public suggestions was posted to the club's website. In August 2015 it was announced that the HeatDevils will compete in the second division of the
B.League, the new league to be created from the bj league and NBL merger. The team hired
Tomoyuki Umeda to replace Suzuki as head coach but fired him in the middle of January after they struggled to a 6–18 record and sat in second-last place in the Western Conference. The team hired
Shinshu Brave Warriors assistant coach
Ryuji Kawai as Umeda's replacement. The team fared better in the second half of the season, posting 10–14 record under Kawai to remain within playoff contention, until consecutive losses to Osaka on April 16 and 17 made it impossible for the team to sneak into eighth spot. In what was to be a fitting end to the team's Oita era, they were scheduled to play their final two games of the season at
Beppu Arena on 23 and 24 April 2016 against the
Kanazawa Samuraiz, who hired Suzuki as coach during the off-season. The HeatDevils finished their final season in the bj league in 10th place in the Western Conference, three games outside of the top eight.
Ehime Orange Vikings (2016–17) To coincide with the commencement of the B.League in September 2016, the HeatDevils relocated its head office to Matsuyama and announced they would compete in the new league as the
Ehime Orange Vikings. The team retained Kawai as head coach and started the season with a 10-man roster that included American imports
Joshua Crawford and
Craig Williams Jr. and
Tatsuhiko Toshino as team captain. After losing their first four games of the season, the team added two small forwards to their roster, Frenchman
Rémi Barry as their third import player and
Shugaku Izumi. ==Record by season==