Trolla is Orko’s home dimension, where the laws of magic operate differently from Eternia’s. On Trolla, Orko is reputedly a competent wizard; the running joke of the Filmation series is that his spells misfire only when cast in Eternia’s incompatible magical environment. The 2021 Revelation continuation gave Trolla and the Trollans a more developed treatment, with consequences for Orko’s character arc.
Catalogue source: heman.fandom.com (CC BY-SA 3.0).