Switching from bass (which she played in Standard Fare) to guitar and vocals, Kupa teamed up with bassist Mark Boxall and drummer Tom Barden to form the combo Mammoth Penguins.

[1][2] The new group's debut single, "When I Was Your Age", was released in June 2015, and their album, Hide and Seek, arrived a month later on the Fortuna Pop!

[1][3] The band returned in 2017 with the "A Simple Misunderstanding" single for Kingfisher Bluez; they went on to make a record that expanded from their earlier punk-pop sound.

[1] Titled John Doe, it featured contributions from Haiku Salut's Sophie Barkerwood (programming/samples), as well as Russell Lomas (violin), and Joe Bear (samples/synths).

[4] Veteran critic Robert Christgau regarded it as "the keeper" in Kupa's discography for how, "commonsensically and prosaically but also fervently and you bet tunefully, she's trying her best and getting better at" relationships, as reflected in the music's narratives.