Hey fellow Final Fantasy X explorer! When it comes to sphere grid progression, focus on unlocking key abilities like Delay Attack and Haste early on to make battles smoother. For side quests, don’t miss out on the Celestial Weapons and Monster Arena challenges for great rewards. As for character builds, tailor each character to their strengths – Tidus for speed and agility, Auron for strength, and Yuna for white magic. Experiment with different paths on the sphere grid to maximize each character’s potential! Happy exploring!