Complex sentence: At the beginning of the series, Zuko is introduced as the main antagonist and who is searching for Aang in hopes of reclaiming his honor, and throughout the season is hot on the Avatar's trail, at times both helped and hindered by Iroh.
Split into simpler sentences: At the beginning of the series, Zuko is introduced as the main antagonist who is searching for Aang in hopes of reclaiming his honor. Throughout the season he is hot on the Avatar's trail, at times both helped and hindered by Iroh.