The following are some recommendations for the opening of the Hunter Series:
1. "One Punch Hunter": Author's Green Shirt Getting Drunk
2. " Siheyuan: Maximum Level Hunter, I'm Hunting!" the authors did not mention
3. " Celebrating the Second Year of the Year's Opening: The Maximum Level Prodigal System ": The author did not mention it.
Please note that the novels recommended above may only partially meet the requirements of the Hunter series at the beginning of the game. There may be other related novels that do not appear in the search results provided.
The theme song might not be the opening song. Although the theme song usually referred to the opening song, sometimes the theme song could be other songs instead of the opening song. Therefore, the theme song and the opening song could be defined and used differently in a work.
The Hunter x Hunter manga is unfortunately not complete. The author has faced various issues that have led to intermittent breaks and an unresolved storyline.
The Hunter x Hunter manga has indeed concluded. However, the ending might have left some fans wanting more or with mixed feelings depending on their expectations.