Hyun was given the moniker "Magic Hippo", "The Lord of the Military", "Point Forward" and "Korean Charles Barkley" for his size, versatility, and dominance.

Hong Sung-hwa (홍성화; 洪性華), his mother, is a former national basketball player, which Hyun was unaware of until his second year in middle school, when she came to watch his game and his coach recognized her.

Billed as a high valued asset for his advantage to leap and shoot the ball as a big man, including his untapped potential in other aspects of the game, Hyun’s recruitment received a wide media coverage.

[12][13] In an interview, Hyun shared that he initially wanted to join Yonsei University, the leading college basketball team at that time, because he can win a championship ring easily without putting a lot of effort.

However, his father, a graduate of Korea University, advised him that looking for an easy path in his basketball career will not help him progress, but instead it will lead to his decline because he will be staying inside his comfort zone and will not be seeing any growth.

[11] Together with Chun Hee-chul, Yang Hee-seung, Kim Byung-chul (Korean: 김병철; Hanja: 金昞徹) and Shin Ki-sung, they were dubbed as Korea University's "Best Five".

[22] In his debut on November 14, 1998, Hyun posted 26 points, six rebounds, eight assists and two steals, leading SK Knights to a 95–94 season-opening win over the Daegu Tongyang Orions.

In a statement, Busan KTF Magic Wings Director Chu Il-seung (Korean: 추일승; Hanja: 秋壹勝) said that there was barely cartilage left in Hyun’s knee.

Eventually, Hyun did not opt for a surgery, instead, he underwent rehabilitation program at Samsung Medical Center for his injured left knee cartilage.

In particular, prolific tall shooters Seo Jang-hoon (of Seoul Samsung Thunders) and Kim Joo-sung (of Wonju TG Sambo Xers) could not score over 10 points against Hyun who was in charge of playing defense against them.

[115][116][117] Hyun, who had been rehabbing his knee and still had a year left on his contract with the LG Sakers, formally concluded his career after nine seasons, in a press conference on June 25, 2009.

Hyun was selected as a Legend for the forward position (alongside Aaron Haynes, Johnny McDowell, Chun Hee-chul, Choo Seung-gyun and Moon Kyung-eun).

[126] Hyun competed for South Korea at the 1993 FIBA Under-21 World Championship, a now defunct age group competition, in Valladolid, where they finished in eleventh place after a 96–87 victory against Chinese Taipei in the classification round.

[130] Hyun was the top performer of the team, averaging 18.0 points, 4.3 rebounds and 2.1 assists over 7 games, while shooting 41.1% from the field, in addition to posting a 73.1% free throw percentage.

[137][138] At the 1998 FIBA World Championship held in the city of Athens and Piraeus, Hyun played for the South Korean squad in four of five games, missing out on the match against Brazil.

[140][141][142] Hyun was named to the South Korean roster for the 1994 Asian Games in Hiroshima, where they finished runner-up, bringing home the silver medal in a 72–100 loss to China.

Despite experiencing pain on his left knee and the doctor’s advice to not participate, Hyun led South Korea to snatch the gold medal from China, headed by NBA player Yao Ming, in a 102–100 final score victory.

[171][172][173] Hyun represented South Korea in the 1999 ABC Championship in Fukuoka, where they finished runner-up, after being defeated in the gold medal game by rival team China with a score of 45–63.

[178][179][180][181][182] Standing at 6 ft 4.8 in (1.95 m) and weighing 284 lb (129 kg),[30] Hyun played the power forward position, a specialized role which was not exhibited in Korean basketball during the 1990s.

[189][190][191] In an interview, Hyun, who had turned down many sports broadcasting offers he had received since his retirement, revealed that he initially said no because he felt he was not yet ready to step inside the hardwood but after he realized that if it becomes too late, he will never be able to come back to the court, which he considers his home, he finally said yes.

[198][199] After the announcement that Hyun will be joining the Changwon LG Sakers as their head coach, he made his last appearance as a broadcaster on April 26, 2017 when he came out as a guest commentator during the third game of the 2016–17 KBL finals between the Anyang KGC and the Seoul Samsung Thunders.

[204][202] In Hyun's first year of coaching, the Changwon LG Sakers ranked ninth out of the ten teams in the league with 17 wins and 37 losses in the 2017–18 season.

[208][209] In an episode of the KBS2 show called Boss in The Mirror which aired on May 17, 2020, Hyun expressed that he resigned from his post because he felt responsible for the team’s lackluster performance in the 2019–20 season.

[211] In February 2015, Hyun, who was active as a basketball commentator, appeared as a guest on the award-winning and most-watched Korean variety show Infinite Challenge, where he got the nickname "Super Power".

Hyun expressed that the aim of his TV appearances is to help rekindle the public’s interest in the sport of basketball,[217] which was overshadowed by the popularity of association football, baseball and golf.

Due to their TV stint, players Kim Si-rae (김시래; 金時來), Kang Byung-hyun (강병현; 姜秉賢), Jeong Hee-jae (정희재), Kim Dong-ryang (김동량) and Park Byung-woo (박병우) became well-known figures in the basketball world as well as the team's general manager Park Do-kyung (박도경; 朴塗景) and translator Chae Seong-woo (채성우).

[222] With Hyun's television activities, he helped in boosting the image of the KBL, especially since the league and its players and coaches had been in the negative spotlight after a series of scandals involving illegal betting, match-fixing and drunk driving from the late 2000s to early 2010s.

Alongside Seo and their former national teammate Hur Jae, Hyun's appearances on television have drawn more attention towards basketball, which had seen a sharp decline in popularity since the 1990s, back when the trio were in their prime.

[201] To devote more time and have an undivided attention in coaching the Changwon LG Sakers, Hyun did not appear in Boss in The Mirror for the whole duration of the 2019–20 KBL season.

[227][228][229] Following his resignation as a head coach of the Changwon LG Sakers, Hyun returned as a cast member of Boss in The Mirror in May 2020 after 6 months of being off-air.