At the beginning of the Kolhii match, the competitors salute each other by saying "play well." Lego, the company that produced the Bionicle toys, takes its name from the Danish phrase "leg godt", which means "play well".
Prior to the movie's release, Cartoon Network held a contest to win the LEGO piece of the titular mask, cast in platinum. This platinum Avohkii was a unique piece, as only one was made. As of the mask's resale on February 16, 2014 for the price of $15,000, it was the most expensive single LEGO piece ever to be sold at the time. When the mask's owner, Andre Hurley married in October 2020, he wore the mask on his wedding suit. This record was upended a decade later on February 21, 2024, when a 14-karat gold Hau mask (the type of mask worn by Jaller in this film and also the original mask of Tahu) was sold at an auction for $18,101. There are 30 copies of this mask, five of which were given away as awards for a contest held in 2001.
After Takua alerts the people of Onu-Koro with the news that Rahkshi have attacked him, Toa Pohatu responds by asking "What is Rahkshi?". In the Bionicle lore, it is a running joke that after hearing a name or expression for the first time, Pohatu always asks what it means. Usually, though, he doesn't get straight answers from any of the other characters.
Though the Bionicle toys had been around for several years by the time of this film's release, the characters were designed to look as if they inspired the toys, rather than being inspired by them: while the animators could have recreated the exact look of the toys, they gave the characters a more biological look.
Makuta's mannerisms were based on those of Colonel Kurtz from Apocalypse Now (1979). Director David Molina also jokingly said Makuta's movements were inspired by his uncle Alan, a really large and scary man who still moved very fast.