Commercially, "Hwaa" became (G)I-DLE's first top-five hit on the Gaon Digital Chart—peaking at number four—and became their first chart-topper on the component Download Chart.

Soyeon said: "The reason I chose to put those two hwa's together is because the song features a narrator who is in winter but will burn the cold away and bloom like a flower and bring spring to them."

"[6] In an interview with Marie Claire Korea for the January edition, Soyeon hinted that the song, "[is] suitable for winter, but it won’t be just cold.

[21] The song sings about the pain of love using the burning fire and colourful flowers in the cold winter sensibility as a metaphor.

[24] An accompanying music video for the song was directed by Paranoid Paradigm of VM Project Architecture and uploaded onto (G)I-dle's YouTube channel simultaneously with the single's release.

Writing for Benedetta Geddo of Teen Vogue praised (G)I-dle's for their "undeniable talent for grand-scale storytelling and visuals in both their songs and music videos.

"[27] Heran Mamo from Billboard describes the song as "ignites one's inner-fire to avoid the cold feelings brought on by a breakup".

He also wrote, he was somewhat amazed how foreign fans found the fully Korean lyrics "appealing" and the "[usage] of oriental instruments" in the song.

[20] Rolling Stone India's Riddhi Chakraborty characterized it as a "dark and dreamy synth-pop" track and acclaimed it "an anthem about moving on from painful memories".

[19] In The Quietus, reviewer Verónica A. Bastardo wrote that the song is "a looping journey between the rhythmic drums of dancehall and open, airy spaces.

The singer's emotional voices, a bright, East Asian-sounding string instrument at the back and wind sound effects make up the details that transport you to a dark unknown wood where you can see flowers bloom even within the fire.

"[30] Lim Dong-yeop of IZM wrote in his review, "(G)I-dle, who have captured the public with their intense images, took out a new card this time."

She deemed the group members as "extremely rare crazy female characters through K-pop, from releasing a charismatic debut song "Latata", [...] bizarre and grotesque horror drama "Put It Straight", [...] breaking down the line between good and bad in "Oh My God" that has long been considered as sacred to female idol, [...] gave themselves the crown of a Lion King instead of a queen [...] After giving a breath of fresh air with "Dumdi Dumdi" during the hot wind summer, (G)I-dle's "Hwaa" revives the fire of the path they have walk in, spreading the fire on the love that they sought as they sing a song of destruction and reincarnation."

"[31] Writing for Beats Per Minute, JT Early described "Hwaa" as it "feels like a winter dusk where the only warmth is from internal rage.

The song is bittersweet, simultaneously acknowledging pain but also detailing a cold heart slowly thawing out giving an ultimate message of hope.

Although the track ends abruptly, this is still a unique and affecting song that only echoes the loneliness and heartbreak many people are experiencing in our pandemic times.

[36] Additionally, "Hwaa" is one out of three fourth-generation girl group songs to reach the top spot on Melon Realtime.

[65] The global entertainment platform Makestar opened the one-on-one video call event page from December 30, 2020 – January 10, 2021, to commemorate the release of the album.

[90] The music video for "Hwaa" was directed by director Paranoid Paradigm of VM Project Architecture production team,[62] and was uploaded to (G)I-dle's official YouTube channel on January 11, 2021.

[97][98][99] The music video opens with a scene where the members meet their eyes in front of a tree that was once lush but dried and twisted.

[100] Singing, "As if a cold winter has struck/the time freezes/and the darkness that seems to contain the brutal wind gets deeper and escapes/Let's erase the endless seasons without weakness/Alone scars on the hot days.

"[91] In the video, Miyeon, Minnie, Soojin, Soyeon, Yuqi and Shuhua showed strong eye contact, weak expressions of resentment towards the parting partner.

[100] Miyeon appeared in a hime cut,[100] Yuqi wearing a short wig,[101] Minnie in bright red straight bangs,[101] Soyeon in silver coloured-hair,[101] and other members' unconventional hair styling using hairpins while carrying props such as umbrellas and fans.

[102][103] The group performed as they were blooming flowers against the backdrop of a cool blue snowy field, while Soyeon rapping in a tree nest.

"[27] Portal Popline's Caian Nunes noted that the music video uses "mix elements of nature with futuristic structures", and moved by "the richness of details in each setting, [...] as well as in the costumes.

(G)I-dle announced a remix of the song by a world-renowned Belgian DJ duo Dimitri Vegas & Like Mike on January 31, 2021.