Hey fellow Final Fantasy X explorer! When it comes to sphere grid progression, make sure to focus on each character’s strengths. Customize their paths to maximize their potential in battle. Don’t be afraid to mix and match different abilities to create unique character builds.

For side quests, be sure to complete the Monster Arena challenges for great rewards and tough battles. Don’t forget about the Celestial Weapons either – they pack a powerful punch once fully upgraded. And lastly, make time for the optional Aeons and secret bosses for an extra challenge.

Overall, take your time exploring Spira and enjoy the journey! There’s so much to discover beyond the main story. Happy adventuring!