Extra HP: 45
Extra MP: 10
Magic Power: 34
Battle Power: 99
Magic Defense: 34
Overview/Stats: Gau is hands down the most complicated character in the game. Most people write him off because it takes so much work to weed through the literally hundreds of bad rages he can get. However, once you know how to actually use Gau, he becomes godly. His stats are some of the best in the game. The only stat of his that is bad, is his Defense, but that doesn't matter much for him anyways. His Magic Power is fifth highest in the game (tied with Strago) and he starts off high M.Block percentage, which is always nice. The only downside to him is that he can't use weapons, so his battle power will always be low (unless you use the merit award) unless you train his Vigor extensively.
Special: There are 255 different rages in the game. With a number that large a couple of those are bound to be broken. I'm not gonna list every single useful rage of his, because that would take up this entire blog post. I will however list the big three: Stray Cat, Magic Urn, and Nightshade. You can go through the whole game building up Gau's Vigor and only using Stray Cat and he'll be an amazing physical damage powerhouse. Magic Urn turns Gau into a hyper defensive character. He will absorb all magic sent his way, is immune to all status effects, and cast Cure 3 on the party continuously. It is pretty hard to die while raging as a Magic Urn. The Nightshade rage makes the entire game laughably easy. This rage allows Gau to cast Charm, a spell which has an 80% hit rate and works everytime on every enemy including bosses (This also includes Kefka). It cast a version of Muddle on them (confusion) which will never wear off unless Gau dies (which he won't). Using the Nightshade rage is basically cheating. Rages are the best special in the game if you know how to use them.
Equipment: Gau can't use any weapons, which is fine because he works well without them. This makes him a good candidate for the Merit Award though, as this relic allows you to put a weapon onto Gau and then suddenly things get absurd. He has access to one of the best armors in the game (Snow Muffler). Other than that, his defensive equipments are nothing special.
If you use Gau right you almost feel like your cheating. His absurd power level puts him in the top tier with Terra and Celes.
Extra HP: 46
Extra MP: 9
Magic Power: 29
Magic Defense: 26
Stats/Overview: Setzer is a character who is a little bit of a one trick pony. Like Locke, Setzer is reliant on the Offering to do good damage in the end game. Unlike Locke however, hes actually quite useful to have around in the WOB. For all intents and purposes, the characters are pretty similar. His stats are pretty average across the board. Nothing really jumps out as anything special or weak. The good thing about Setzer though is that his special and ultimate weapon do not use Vigor at all, so you can raise his Magic Power throughout the game without worry, making him a good physical fighter and decent backup spell caster.
Special: Again, slots is one of those specials that gets worse as you progress in the game. It is pretty easy to get the timing down on 7 Flush and Chocobop, and both are very good attacks in the WOB. The rest of his slots are actually rigged against you, so you can't rely on them for damage in the WOR. GP Rain is awful, so don't bother with it.
Equipment: Setzer has a very unique type of weapon in his Cards, Darts, and Dice. They are mostly long range, so he can always be in the back row safely. They usually have some sort of decent status effect attached to them too, which is also nice. His main draw however is the Fixed Dice, which randomly does good damage and it always hits and ignores defense. This makes him a good candidate for the Offering, since the Fixed Dice ignores the Offering's damage penalties. His armor is nothing special, its similar to Locke and Shadow's. He can use the Force Armor though, which is nice.
Overall Setzer is a lot like Locke; He is reliant on the Offering to do decent damage in the end game. This makes Setzer is mid tier character.
Extra HP: 35
Extra MP: 13
Magic Power: 34
Battle Power: 10
Magic Defense: 27
Overview/Stats: Strago is a good example of a character gone wrong. He is the first character you get you actually screams that he should be a Mage. The problem is that as a Mage, he makes a pretty mediocre one. His Magic Power is tied with Gau for fifth highest. Mog has a higher magic power than he does! His physical stats are abysmal, which is to be expected. For an ancient mage warrior, he can't even fling spells as well as his 10 year old Granddaughter.
Special: Lores are pretty awesome. Aqua Rake is better than a lot of other spells in the WOB. The problem with Lores is that everything they do, the Magic skillset can generally do better. Having both Magic and Lores is a little bit redundant, as their effects aren't dissimilar enough from each other. On the plus side, he can hit some of the more obscure weaknesses like Water and Wind.
Equipment: His equipment isn't anything special. His ultimate armor, the Behemoth Suit, is good, but it outclassed by the other ultimate armors (namely the Minerva, Snow Muffler, and Force Armor). The Magus Rod isn't bad, its sorta like an improved Enhancer sword. Not much else to say here, his equipment is remarkably average.
Strago is supposed to be one of the game's dedicated mages, however his stats ensure that he'll always be a mediocre one. Lores aren't very useful as a whole, and his equipment options are average at best. If you need a mage, just go with Terra, Celes, or Relm. Strago is a low tier character.
Extra HP: 37
Extra MP: 18
Magic Power: 44
Battle Power: 11
Magic Defense: 30
Overview/Stats: Who has the highest Magic Power in the game? Its not Terra like most people think, but Relm. She actually beats Terra's Magic Power by quite a lot. She is one of the most underrated characters in the game, and is the best dedicated mage out there.
Special: Sketch is terrible. Its up there with Runic as one of the worst specials in the game. It is also poorly tested and can cause all sorta of nasty glitches, so its just best not to use it. Control isn't much better. Just have Relm shoot some fireballs and be done with it.
Equipment: Relm can use everything Strago can use plus the female specific equips, making Relm's equipment selection quite good. Like Strago, she has access to the Behemoth suit and Magus Rod, which are both fine in thier own right. She gets the Cat Hood, which is hands down the best helmet in the game. It has good stat boosts, amazing defense, halves all magical damage, and lets you earn more GP in battle. Plus, shes the only character that can use it. In addition, she is the only character who doesn't wield a sword that can reach 128% M.Block easily.
Relm starts the game off awful. Once you teach her some decent spells though, she'll become a force to be reckoned with for the entire game. Relm is high tier, not really because of her own merits, but mostly becuase Magic Power and the Magic skill set are overpowered in general.
Extra HP: 60
Extra MP: 0
Magic Power: 37
Battle Power: 47
Magic Defense: 68
Overview/Stats: There isn't much to say about Umaro. He starts off strong, but since you can never equip him, the damage he deals when you first get him will never really change. So while he starts off decently enough, he gets outclassed by everyone else quickly. All of his stats starting stats are good. Too bad you can't raise them ever.
Special: You can never control Umaro, so he's permanently in Rage mode, which is annoying. Later on you can get the Rage Ring and Blizzard Orb which allow Umaro to throw characters and to use the special skill Blizzard respectively. Unfortunately both of this skills are mediocre and random to boot.
Equipments: He comes equipped with a Snow Muffler on, which is nice.
Overall, Umaro is a character who does good damage when you first get him but will never really improve. This coupled with the fact that you can never control him, makes him a low tier character, and more of a novelty than anything else.
Extra HP: 36
Extra MP: 12
Magic Power: 26
Battle Power: 13
Magic Defense: 25
Overview/Stats: Gogo is a character who can do everything, just not particularly well. His stats are some of the lowest in the game, and they can never increase. This is his main drawback, as without it Gogo would be overpowered.
Special: Mimic is fun for novelty purposes but not for anything else. The best part about Gogo is that he can use every special in the game except for Morph. This makes him incredibly versatile. Need another thief? Done. Want another Bum Rush user? Done. Want to have two Magic Urn ragers at once? Done. This is Gogo's main selling point.
Equipment: Gogo's equipment selection is bad. He can use most of what Strago can use, except for the suits. The good thing about Gogo is that he has very mage like equipment selections, which means its easy to raise his magic power. Technically, he can end up Bum Rushing better than Sabin can.
Gogo's extreme versatility make up for his terrible stats. This makes Gogo a rather average character (mid tier), as he'll always be useful but never really good at anything.
Top Tier: Terra, Gau, Celes
High Tier: Edgar, Shadow, Mog, Relm
Mid Tier: Locke, Setzer, Sabin, Gogo
Bottom Tier: Cyan, Strago, Umaro