YMMV / Star Ocean: Blue Sphere

• Big-Lipped Alligator Moment: Rival suddenly becoming Lenneth Valkyrie during the final battle is completely random and makes no sense whatever.
• Demonic Spiders: Dragon Warrior and its palette swap Millennium. Both are very dangerous enemies to fight and hard to avoid because they teleport right in front of you.
• Goddamned Bats:
  • Ants have low HP, but their small sprite makes them annoying opponents to deal with normal attacks. They're also hard to see in the field map.
  • The floating orbs are annoying to fight due to their habit of attacking and retreating when your melee fighters approaches.
• Spiritual Successor: The field map exploration is similar to The Legend of Zelda: A Link to the Past. Like in Zelda, the dungeons are made up of multiple rooms "linked" to each other (it even uses the same type of screen transition) and there are puzzles involving special tools, like bombs to break objects or find hidden passages.
• That One Level: Being a Dungeon Crawler, no level in this game is a walk in the park, but the Leviabor Ruins (revisited) is something else. In order to proceed, you need to find TEN Plot Coupons hidden in the various floors... and to get these coupons you'll need other TEN special items that cause the chest/secret room containing the coupons to appear. You also need to find some batteries to solve a puzzle in one of the lower floors. While the normal enemies are underleveled and can grant a fair amount of SP, the amount of backtracking and the frustration of not knowing where to go without a guide makes this a solid contender for the worst level in the Star Ocean series.
• That One Puzzle: The elevator switch puzzle in Grand Knot (right after Cosmo City) is very annoying and rellies on trial-and-error, as there is not way of knowing which doors will open/close when you use an elevator without using a guide.
• Unexpected Character: Lenneth Valkyrie isn't that unexpected since this is a tri-Ace game, but Lenneth Valkyrie as one of the final boss transformations sure is.