The story is told by the poem's original author János Arany (voiced by Tamás Széles who also plays all other characters), who appears throughout the series as a ghost addressing the audience. His appearance was based on a famous sketch that another classic poet, Arany's good friend Sándor Petöfi had made of him in one of his letters, which is why he only moderately resembles the real Arany.
Though most of the series is based verbatim on the text of the original poem, some alterations and additions were also made. Only about 70% of the poem is heard, as it was decided that some verses worked better if told purely by the visuals. Many silent scenes were added to balance out the pacing, showcase more of the characters and the environments of medieval Hungary, mainly the great rural plains and swamps. When Toldi returns to his house as a fugitive, her mother tends to his wounds and gives him clean clothes, which did not happen in the poem. The poem also incorrectly referred to Hungary's capital by its modern name Budapest, but at the time the towns of Buda and Pest had not yet been merged, which is also corrected in this series.
The final work of legendary Hungarian animation director Marcell Jankovics. He had retired from directing after The Tragedy of Man (2011) to focus on more personal projects and was initially reluctant to accept the studio's proposal to direct one final animated series, especially since the Toldi poem had already been adapted into animation in Daliás idök (1983). Jankovics eventually agreed to the offer as he believed he could find a unique way of adapting the poem. The series was finished and given early access screenings during his life in late 2020, but it was only released to the public four months after he had passed away. The series was dedicated to him.
Whenever Toldi is infuriated, he becomes more buff and his hair bursts into golden flame, which had lead to comparisons and internet memes about the Super Saiyans of Dragon Ball Z (1989). In actuality, Toldi's transformation is only a visual metaphor and a possible reference to the character Fanyüvö or Treeshaker from the director's film Son of the White Mare (1981), whose hair was made out of fire.
The series was financed by the Hungarian state. Its production reportedly cost around one billion Hungarian Forints (almost $3,648,000 at the time), over twenty times the usual annual budget of Hungary's entire animation industry.