These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Complete Monster: Admiral Galcian is loyal to one thing only: power. When first seen Galcian is the Dragon with an Agenda to the nation of Valua and its empress Teodora. A ruthless man who tries to wipe out Vyse and the heroes at any cost, Galcian pursues an agenda of hunting down moon crystals to enhance his own personal power. After finding the superweapon he's been looking for, Galcian reveals his true colors and uses it on Valua, his own nation. His reasoning is that if he obliterates the most powerful country, the other nations will fall in line. While he is a man capable of inspiring loyalty, Galcian possesses none for anyone but his own power and advancement.
Cult Classic: Few have heard of the game and even fewer have played it, but damn near everyone who did loved it.
Ensemble Darkhorse: Many minor characters make the cut, such as Belleza and Gregorio with their Heel Face Turns, as well as crew members such as Don, Hans, and Lawrence. However, most fans would agree that the best example is Gilder, a womanizing, Badass Longcoat and Cool Shades wearing Gunslinger. He even acts as The Lancer for Vyse. Ilchymis is liked by anyone who has taken the trouble to find him and use the ability to buy an unlimited number of attribute boosts from him.
Escapist Character: Gilder. Too cool to be real and yet, a fan favorite. See above for the reasons.
Justice Shield halves the damage from the majority of attacks.
Delta Shield blocks all magic attacks and is invaluable against instant death attacks.
Pirates' Wrath deals massive damage for a not-unreasonable amount of SP.
Skull Shield makes your party immune to all physical and magic damage for one turn, but still leaves you vulnerable to staus ailments. In addition, if the enemy uses a physical attack against any of your party members, while Skull Shield is active, it responds with an automatic counter attack. This allows you to kill Loppers easily. Simply activate Skull Shield, then sit back and laugh as the loopers kill themselves while trying to attack you.
Lunar Light fixes everything. It heals everyone to max, revives all fallen allies with max health, AND removes all status ailments, all in a nice 18 SP package. By the time you're able to get it, you'll be generating that much in two turns, tops.
Better. Recruit Ilcyhmis, upgrade the item shop at your home base, and he'll be able to sell you seeds. As in, the items that provide the given party member with a permanent stat boost. And given the Money for Nothing nature of this game, you can very easily pump your party members full of seeds and transform them into stupidly broken Arcadia-walking deities.
The Magic Shells used by your ship are completely unblockable, allowing you to do things like cast Silence on the final airship boss (who mostly spams magical spells).
Goddamned Bats: Loopers, in all their forms. They're nearly impossible to hit with normal attacks, are immune to magic, their defence power is high enough that Lambda Burst usually deals 0 damage to them, they frequently buff the other enemies in the battle, and often run away before you can actually hit them with a Special attack and/or kill them, especially early in the game. Ironically, they're more likely to die if they attack you than if you attack them, since your counter-attack rate is likely to be higher than your hit rate against them.
Skull Shield lets you pwn Loopers easily, as noted under: Game Breaker. Vyse's "Rain of Swords" also kills Loopers, since it deals non-elemental damage.
Hell Is That Noise: The BGM for the Dark Rift and Deep Sky. It sounds soothing, but has odd dark undertones that turn it from relaxing into unsettlingly ambient. The oddly triumphant-sounding part at the end of the loop adds to the eeriness. Also, it's not on the OST.
Magnificent Bastard: Galcian still controls the Valuan Armada, in spite of the fact that he just erased their homeland off the map.
In the beginning of the game, Alfonso kills his Vice-Captain in an effort to keep his reputation intact. It perfectly sums up what kind of villains you'll be dealing with in this game.
Galcian crosses this when he summons the Rains of Destruction on Valua.
This is mentioned backhandedly in a conversation with a minor NPC, but Ramirez gets one when he has the entirety of the Nasr Royal Family dragged off to be executed for the amusement of Valuan citizens.
One True Threesome: Not an unheard-of interpretation of the main trio's relationship, given how close they are as a trio by the end of the story. The game proper doesn't have anything conclusive to say about romance among them in any case, which is probably why Ship-to-Ship Combat is very rare among the fanbase.
During the final encounter where Ramirez's fused with Zelos, Silver Nightmare, which allows him to possess a member of your party for one turn and use the character's own offensive S-Moves against the rest of the party. The move has 100% accuracy and automatically preempts every other attack and defensive S-Move; it can range from moderately annoying (if he possesses Fina and uses Lunar Winds) to very, very dangerous (if he possesses Vyse and uses either Rain of Swords or Pirate's Wrath). Most of his other S-Moves cause high damage, but are relatively easily countered.
Not the first That One Attack that Ramirez has either. You will quickly come to dread hearing the words
Ramirez: Where there is light... THERE IS DARKNESS!
Legendary Punch and Berserk Rupee if you were stupid enough to attack Rupee first.
How the bloody hell did Lapen build a Moonstone Cannon?
The Ixa'ness Demons' Chak Mal, which deals heavy damage to all characters and often inflicts various status effects.
Golden Flurry. Deals relatively high damage to all characters and has a good chance of inflicting Confuse.
Belleza, in her flagship the Lynx. Potentially the third ship battle in the entire game, not counting the preceding Hopeless Boss Fight, Belleza is also the first to make strong use of both torpedoes and a magic cannon, buffing herself and combining her attacks for heavy burst damage. A good combo from her can knock upwards of 7,000 health off the Little Jack's 10-11,000 HP pool in a single round. To make matters worse, you fight her immediately after the Temple of Pyrynn and Recumen, so it's unlikely that you'll start the fight in good shape unless you start the battle knowing the trick to avoid damage.
Vigoro. The first time you fight him he isn't all that hard, but he tells you that you only won because he didn't have his cannon or his armor at the time. When you fight him the second time, where he does have his cannon and armor, you find out he wasn't really kidding.
Lapen. Let's see...he summons three durable mooks at a time that can each cause relatively high damage. He has an immensely powerful area attack that can easily knock out several characters, even with damage-mitigating special moves in play. He has a single-character attack which usually causes instant death. Good thing you saved an Aura of Valor so that you can instantly get a Prophecy off on him. Right? ...Right?
Piastol: She's lightning quick, her Deluge S-move showers the party with dirks (which have a 45-50% chance of petrifying multiple targets), her Tempest Dance is almost certain to kill whoever she uses it on (unless you've used Justice Shield beforehand), and she can spam Eternum. Worse, her Deathhound casts Speed and Incremus on her, to increase her already ludicrous speed and attack power. Plus, it can heal her with Sacres (upgraded to Sacrum, during the final encounter), or poison you with Noxus. And, if all of that wasn't enough, she gets harder with each encounter! Be prepared to spam both Delta and Justice Shield every round... OR ELSE.
That One Level: Moon Stone Mountain. Feel free to rage at the memories of falling through floor tiles and having to walk all the way back again.