Production
The first Splatoon performances were directed by Yuki Hashiguchi and the mononymous dancer and disc jockey (DJ) Melochin. Hashiguchi was enlisted for his past work with Dwango directing live events for Vocaloid characters and VTuber personalities. He reached out to Melochin, a longtime acquaintace, because he believed the mood of the Splatoon events matched her free-flowing musical identity; he did not want the music to be confined to hip hop or rock, for example. Additionally, Melochin herself was a devoted Splatoon fan who purchased the Wii U solely to play it. He also enlisted the help of bassist Tetsuma Oyama to arrange the events' songs. Hashiguchi stated that the team grew to trust one another and become capable of delivering high-quality performance without explicit directions, bolstered by a shared love for Splatoon.
Choreography and motion capture
For the first-ever concert featuring Callie and Marie of the Squid Sisters, Hashiguchi used a concept created by the Dwango team as a starting point for dialogue with Nintendo. Once the overarching flow and chorus was finalized, Melochin was instructed with composing a rough idea for the choreography for the Squid Sisters that would be sent to Nintendo for comment. She jointly used Oyama's arrangements and her own intrepretations of Splatoon as inspiration for composing the duo's dances. She recalled struggling with slower-paced songs, one of which, "Maritime Memory", had to be completely redesigned. Callie and Marie required more detailed choreography compared to Pearl and Marina of Off the Hook, and revisions were guided by Nintendo's own critiques.
Melochin also served as the motion capture actress for Callie, Marie, Pearl, and Marina. In describing how she approaches portraying each character, she characterized Callie as energetic, Marie as meticulous, Pearl as free-spirited, and Marina as fluid. To embody the characters, Melochin would tell herself phrases such as "Okay, Callie", "Next, Marie", "Pearl's here!", and "Marina's coming in!" She spoke of Pearl as being especially fun to portray, while Marina's swaying movements caused occasional discomfort. Melochin did not consider her performances for Pearl and Marina as being akin to "acting", solely to show off the choreography, but rather as a way to energize the audience and song.
The movements of Callie and Marie were relatively synchronized to convey a complete unit, while the specifics of certain dance moves, such as their playfulness, were modified to reflect the two's distinct personalities. Pearl and Marina meanwhile moved independently of each other, and the non-dancing portions of the performances were improvised by Melochin. She credited her past experience as a DJ and keyboardist as improving her accuracy when portraying Marina using her keytar. For the concert that premiered the song "Nasty Majesty" from Splatoon 2: Octo Expansion (2018), Melochin replayed the final boss of Octo Expansion to replicate the energetic, side-to-side dance moves that Pearl employs during the fight. During the performance, Pearl uses the "Princess Cannon" to fire a large laser beam directed at the audience. The team achieved this by borrowing a large fan and using a combination of light, wind, and smoke to create a blasting effect. The final song Melochin choreographed for the event was "Fly Octo Fly", as a culmination of her directing experience up until then. In a choreography that took only ten minutes to create, Pearl and Marina performed gestures resembling a multitude of weapons from Splatoon 2's multiplayer.
Arrangement
For the Off the Hook-centric "Haikalive" event, Oyama proposed combining the group's trademark genre of electronic dance music (EDM) with the feel of a live band performance. He insisted that a guitar be included to more effectively bridge the gap between EDM and live band; he also wanted to avoid making Off the Hook's songs too distinct from the Squid Sisters'. Oyama sought to create a distinct form of EDM, without explicit emphasis on beat or dance, that he likened to digital rock. The setlists that would be performed onstage by a band was decided together with series sound director Toru Minegishi.
Oyama found that the arranging process was relatively intuitive. He summarized the Splatoon games' relationship with diegetic music as songs that exist because of the games and which enhance said games. In observing this, he wanted people unfamiliar with Splatoon to enjoy the concerts for the music alone, and existing Splatoon fans to effectively relive the games through the music. The single song that Oyama spent the most time arranging was "Fresh Start", a song from the single-player campaign of Splatoon 2 (2017). He held a special attachment to the song as he had then recently completed the campaign, and wanted to make the audience emotional as well. To do this, he emphasized a backing piano track to elevate the song's sentimentality. He created about five to six renditions of "Fresh Start" in total.
