Park Se-yoon ( Hangul: ), more commonly known as Crucial Star ( Hangul: ), is a South Korean rapper, singer-songwriter, and producer currently signed to C-JeS Entertainment. He began his career at the age of 17, as a member of the hip hop group Libra Twins.  
Park Se-yoon was born on October 16, 1989 in
Seoul, South Korea. His father is the painter Hang-Ryul Park. 
He made his musical debut at the age of seventeen in the hip hop group Libra Twins.
Several years later, he signed with independent hip hop label  Soul Company, working under the name Crucial Star. He and label mate  Mad Clown collaborated on the digital album Mad Clown VS Crucial Star in 2010. The following year, he released his first  EP, A Star Goes Up, and his first full-length album, A Star From The Basement.  
Following the dissolution of Soul Company in 2012, Crucial Star moved to Grandline Entertainment.
 While with Grandline, he released two mix tapes,  Drawing #1: A Dream Spokesman (2012) and Drawing 2: A Better Man (2013), two albums, FALL (2012) and Midnight (2014), and one EP, Boyhood (2015).    
In 2015 he appeared as a contestant on
Mnet television rap contest . He was eliminated in the preliminary round after forgetting his lyrics. Show Me the Money 4 In October 2015, Crucial Star's agency  C-JeS Entertainment published a statement announcing that he and contestant Unpretty Rapstar 2 Heize were in a relationship. A week after this announcement, it was reported that they had broken up several months prior.  
He left Grandline Entertainment in January 2016 when his contract ended.
In April, he signed with  C-JeS Entertainment. 
Albums and EPs
(Libra Twins) Love & Fear Released:December 14, 2007
Good Bye Ma Lady (Feat.
Jepp Blackman) Good Bye Ma Lady (Inst.)
Mad Clown VS Crucial Star Released January 29, 2010 
I Just Want U
iPod Girl (ft. Pento)
A Star Goes Up Released: January 27, 2011
It's My Turn (ft.
Zion.T) Trendsetterz (ft. Basick)
Tonight (feat. Satbyeol)
Change Of My Life (Interlude)
Change Of My Life (ft. Dok2 and The Quiett)
New Generation (ft. Pento)
? (Rebirth) (ft. Donutman)
(Bonus Track) Phone Number (ft. The Quiett and Kebee)
A Star From The Basement Released: August 4, 2011 Chapter 1 - The Question
What's This Art For
SCR (Super Crucial Rap)
Chapter 2 - Mind Travel
What's Your Name (ft. Swings)
No More Romance (ft. )
One Better Day
I Just Wanna (ft. CZA)
Chapter 3 - Love, Dream & Happiness
(Can't Go Out) (ft. Donutman)
Chapter 4 - Hope Blooming in Despair
No Pay No Gain (ft. Jerry.K)
Stupid Love Song
Chapter 5 - The Cure
Deep In A Dream (Outro)
From The Basement (ft. B-Free, JJK and The Quiett)
Drawing #1: A Dream Spokesman Released: May 18, 2012 
A Dream Spokesman
Under The Sheets (ft. Donutman)
Doin' My Thang
? feat. Lovey
Headset (ft. CZA)
G.L. (Good Life) (ft.
Geeks, Take One and DJ Eager) Like It Like That (ft. Donutman)
FALL Released: November 27, 2012
One Life 2 Live
Real Love (ft. )
Own Way (ft. Take One, The Quiett and
Zion.T) ? (ft. Rimi)
Flat Shoes (Brother Su Remix) (ft. Lovey)
Nothing Lasts Forever
Drawing #2: A Better Man Released: November 25, 2013
C'est la vie (Intro) (Prod. G-Slow)
FISB-(Future is So Bright) (Feat. Donutman, CZA)
I'm Still #1
25 (I still don't know why)
Chillin' (Feat. Fana, Heize)
Olltii) A Better Man
Feel Like I'm Back (prod. GRAY) (Bonus Track)
Big Dream (prod. DJ Doplamingo) (Bonus Track)
A Winter Love Song Released: December 17, 2013
A Winter Love Song
It's Your Boy (Feat. CZA. Donutman)
Midnight Released: October 16, 2014
Midnight (Feat. Taylor)
(Become A Man)
(Busy Man) (Feat. Louie Of Geeks)
Pretty Girl (Feat. Lovey)
Dreams Forgotten (Interlude)
(Feat. Bob James, Mayson The Soul)
Owl (Feat. Donutman)
Sweet Life (Feat. Konsoul)
I`m The One
Same Boy (Feat. Loco)
Boyhood Released: 6 May 2015 
? ? (My Glider)
AIA (Feat. )
Pet (Feat. Stella Jang)
(The Youngest Son)
Boys to Men (Bonus Track)
Digital singles Catch Me If U Can [October 11, 2010]
 Champagne [September 16, 2011]
 Nothing Lasts Forever [December 11, 2011]
 Super Crucial Rap 2 [February 3, 2014]
Three Things I Want To Give You (ft.
Sojin of Girl's Day) [March 10, 2014] Show Me Your Light (ft. Shin Ji-soo) [April 15, 2014]
As a featured artist Andup - That Girl (Feat. Crucial Star)
Animato & DJ Tiz - I'm Yours (Feat. Crucial Star)
Bang Yong Guk of B.A.P/Jepp Blackman - Last One (Feat. Crucial Star)
Basick - You Already Know (Feat. Crucial Star)
Born Kim - (Feat. Jolly V, Crucial Star)
CZA - Oh Lord (Feat. Crucial Star)
Dok2 & The Quiett - iPhone Girl (Feat. Crucial Star)
DJ Dopsh - Grandliner's Cypher (Feat. Crucial Star, Louie of Geeks, Take One)
DJ Wegun - It's Alright (Feat. Crucial Star)
Donutman - Do Your Thang [Lil'wayne - No Love](Feat. Crucial Star)
Donutman - Love (Feat. Crucial Star)
Donutman - Stuck On You (She Said) (Feat. Crucial Star)
Exy - ? (
Wipe Out) (Feat. Crucial Star) Fatdoo - ? (Feat. Newchamp, Crucial Star)
Fatdoo - 16 (Feat. Crucial Star, Joker, Italian BOB)
G-Slow - I Can't Live (Feat. Crucial Star)
Giriboy - (Feat. Crucial Star)
GRAY - (Feat.
Zion.T, Crucial Star) Geeks- Remix (Feat.
Ugly Duck, , Zion.T, Crucial Star, Zico of Block B, DJ Dopsh) Geeks- In Front of Your House (Feat. Crucial Star)
Heize - ? ? (Feat. Crucial Star)
Innovator - Drama Girl (Feat. Crucial Star)
Jerry.K - Gentleman's Affair [Scary'p - Take Off) (Feat. Innovator, Crucial Star)
Jerry.K - We Made Us Remix (Feat. Crucial Star & Takeone)
JJK - (Feat. Crucial Star)
Lil'boi of Geeks - Star Is Born [Chris Webby - Bounce] (Feat. , Crucial Star)
Loptimist - Sunshine (Feat. B-Free, Crucial Star)
Loquence - Can Can't (Feat. Crucial Star)
Loquence - Change Of my Life Remix [Crucial Star - Change of my life) (Feat. JJK, Crucial Star)
Loquence - Girlfriend (Feat. Crucial Star)
Mad Clown - Stars (Feat. Crucial Star)
Mad Clown - (Feat. Crucial Star)
Minos In Nuol - Oh, My God [Remix 2](Feat. Mad Clown, Crucial Star, Yoosoo)
Qwala - Put It Down (Feat. Crucial Star)
Swings - For Mother (Feat. Crucial Star)
Take One - ? (Feat. Crucial Star)
Take One - Grandline Cypher (CD ONLY Bonus Track) (Feat. Geeks, DJ Eager, Crucial Star)
The Quiett - The Inspiration Remix (Feat. Crucial Star)
Yankie - Love (Feat. Crucial Star, Paloalto)
Young Lion - End Up Fuckin (Feat. Crucial Star)
? - It's Done (Feat. & Crucial Star)
? (SORIHEDA) - Let It Go (Feat. Mad Clown, Crucial Star)
^ a b
"C-JeS Entertainment welcomes hip-hop artist Crucial Star to the family". Koreaboo. 2016-04-07 . Retrieved .
^ a b c d
"Artist Spotlight: Crucial Star". KultScene. 2014-10-03 . Retrieved .
" , ? '?' " [Rapper Crucial Star is "Meditative Artist" Park Hang Ryul's Son] (in Korean). 2013-12-10 . Retrieved .
", '. '" (in Korean). 2010-02-04 . Retrieved .
"[Review] 'A Star Goes Up' by Crucial Star". All Kpop. 2011-02-13 . Retrieved .
"[Drop Watch] Crucial Star - A Star From The Basement". KHIPHOPPER. 2011-07-25 . Retrieved .
", " [Crucial Star Joins Grandline Entertainment]. Hiphop Playa (in Korean). 2011-12-30 . Retrieved .
"Crucial Star releases first mixtape 'Drawing #1: A Dream Spokesman. '" All Kpop. 2012-05-18 . Retrieved .
"Rapper Crucial Star releases album 'Fall. '" All Kpop. 2012-11-30 . Retrieved .
"Crucial Star releases new album, "Midnight" - Koreaboo". Koreaboo. 2014-10-17 . Retrieved .
"Crucial Star to return with "Boyhood" album". Koreaboo. 2015-05-03 . Retrieved .
"Show Me The Money 4 - Episode 1 Recap". Seoul Rebels. 2015-07-01 . Retrieved .
"Crucial Star and 'Unpretty Rapstar' Heize revealed to be dating". All Kpop. 2015-10-06 . Retrieved .
"Heize and Crucial Star Confirmed to Have Broken Up". Soompi. 2015-10-12 . Retrieved .
" , ? " [Crucial Star's and DJ Dopsh's Contracts with Grandline Entertainment Expire]. Hiphop Playa (in Korean). 2015-11-25 . Retrieved .
Crucial Star. "Mad Clown VS Crucial Star". koreanreloaded. koreanreloaded . Retrieved 2015.
Star, Crucial. "Crucial Star reveals tracklist for Boyhood". hiphopkr. Lena . Retrieved 2015.
^ Catch Me If U Can, October 11, 2010 (digital single), at
^ Champagne, September 16, 2011, at
^ Crucial Star, Free Single 'Nothing Lasts Forever' Revealed, at