Deneb Rhode, the Cute WitchMad Scientist, the only character to appear in every game in the series.
Person of Lordly Caliber features werewolf Biske La Varet.
Canopus in Let Us Cling Together, as well as Aloser. The PSP remake of Let Us Cling Together has Ravness Loxaerion.
Evil Is Cool: The two Death Templar of the series, Lans Tartare from Let Us Cling Together and Richard Glendale from Person of Lordly Caliber.
Why is Shiven so Out of Focus if you take the "B" path in Knight of Lodis, whereas the other mutually exclusive character (Orson) gets closure? It's actually a justified example of "Out of Focus", since he's a ninja who was hired to spy for Cybil - so he was actually intentionally off-screen.
Why does Vyce have such drastic personality shifts depending on your participation in the Balmamusa massacre? Simple: because his jealousy is a two-way street, even when he makes the "good" choice not to join in on the massacre.
In Person of Lordly Caliber, almost every character is referred to by generic terms like "warrior" or "old woman" before their names are dropped in-dialogue. When the Zenobians appear again in Chapter One, though, they're all labeled by name despite never introducing themselves. Why? Because their defeat of the Zeteginean empire is famous—Magnus already knows who they are, just not why they're in Palatinus.
Haborym in Tactics Ogre may count. He's a good Swordmaster, but due to his initially high Dexterity (and high growth too), all his status magic has high chance of hitting. So give him a Petrify spell (even if he has Fire affinity) and watch as your enemies turn to stone with nobody to cure it.
Archers are almost game breaking from the beginning, what with extended range on high ground and no counter attacks.
More likely offenders are every single thing found in Hell Gate. Dragon magic hits every enemy on the map, or creates grossly overpowered swords, or lets you infinitely reset a character to lvl 1 without losing stats (yes, you can repeat this for unlimited stats), etc. If you even get partly into Hell Gate the end battles will be easier than the first battle in the game as a result of all the game breaking booty you acquire.
Canopus in Let Us Cling Together, moreso in the PSP version since Archers got toned down. Canopus flies, is an extreme crack shot and has an overall powerful stats, including good dodging rate. He's been called a mini-Orlandu this way.
Drakonite magic in Person of Lordly Caliber. Also, items that raise stats upon level-up.
For the Tactics Ogre PSP remake, if you choose the Chaos route... Vyce will kill the new girl Ravness right off the bat. Which is: Pick who's gonna die, Ravness (and Ozma later) or Sisteena & Selye.
In Tactics Ogre, some of the bosses may make you think "My God, What Have I Done?" Not only do you wind up accidentally fighting your own countrymen if you screw up, but a couple death quotes may be sad. For example, one boss dies and mentions that he can't get medicine for his sick daughter now. You find someone wants revenge for killing her husband a while ago... and starts off by stating that she's pregnant, so you're killing her and her baby. Oh, and the wife's an optional battle, but avoid that, and in Chapter 4, you'll be notified that Sisteena (the girl who briefly appeared in Chapter 1) was Olivia's sister and that wife was holding her captive, sold her to someone and she got killed.
A lot of the time, a single line will be enough to turn a victory into one of these. One boss says "If I'd had that 30,000 Goth... I could have saved my daughter's life" before kicking it.
From Person of Lordly Caliber, if you choose to follow orders, there's Baldwin killing Ankiseth.
Tactics Ogre plays this one rather straight with Plancy's death and Denim convincing Kachua to not take her her own life. Or slaying Guildus in the Neutral route. Or Lans Hamilton's final fate.
There's also the canon ending for Tactics Ogre: The Knight Of Lodis. See the Downer Ending above.
The deaths of Ankiseth, Dio, and Yumil in Person of Lordly Caliber. The first two are avoidable; the last one isn't.
Killing all the Zenobians in Person of Lordly Caliber's secret final level.
Naris in Knight of Lodis, due to his ability to randomly One-Hit Kill with Hell's Gate.
For Person of Lordly Caliber, there's Ariosh (mainly for his ogre) and Amrius (for his Dark Lore).
They Changed It, Now It Sucks!: Nostalgic fans are already complaining about the name changes in the PSP remake of Tactics Ogre: Let Us Cling Together. Some name changes make sense, such as "Zenobia" to "Xenobia;" however, some others (e.g., "gun" to the much more specific "fusil") were straight out of left field.
The Dark Knight Volac Winzalf. His race is indistinct, and due to his surname, there are rumors that he hailed from Zenobia's Highlands, and may have links between Hikash, Rauny or Guildus. He's also one of Lans Tartare's most trusted aides. He spends his time just on Tartare's side, never participating in any battles, and unlike Balzepho, has no bonus scenes and still fewer canon scenes, thus we never really know who he really is.
Also, Andoras mentions a lot of stuff such as how he is a member of the Nirdam royal family but it's not elaborated too much in the game. (These details are introduced in the final dungeon, and only if you have certain party members in the battle!)
Vapula in Person of Lordly Caliber is a former comrade of Debonair's from his March of the Black Queen days who defected from Endora's army, but this is an easily-missable bit of info only brought up moments before he's killed.
Too Cool to Live: In Let Us Cling Together, Neutral Leonar actually becomes a sensible leader, loyal knight who cares about the land after Ronwey's death. Many fans have been clamoring that he should've been recruitable in that route, but alas, he's destined to be killed by Catiua with a stab of knife.
Chaotic route in Let Us Cling Together. Just when Ravness could've followed things right with her heart, Leonard reveals her half-Gargastan route... then Vice kills her on spot. You'll probably feel sorry for her at that point.
It’s hard not to feel sorry for Cressida in the chaotic route. Not only does she lose her sister, mother, and possible brother-in-law from war, her father doesn’t seem the least bit concerned about it. While Nybbas’ two other children have each other, Cressida is all alone with no one but herself.
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