Berserk Button/Fullmetal Alchemist

The cast of Fullmetal Alchemist have so many recorded Berserk Buttons that it practically requires separate folders for each one. "Ed: You know...there are some lines you really shouldn't cross."
 * Edward Elric
 * Perhaps Ed's most famous Berserk Button is any mention of his vertical deficiencies. He usually ends up exaggerating the insult to ridiculous extremes as well as whooping the ass of the offender.
 * The only one he won't go nuts on is Al (after all, they're brothers...and someone has to keep him in line), and even he got away with a knock on the head and a retort of "Don't call me small." Of course, the short rants are constantly a Crowning Moment of Funny.
 * Also, don't suggest that Winry is his girlfriend. At the same time, however, don't even think about harming a single hair on her head...because Ed will kick your ass. Like the narrator in Brotherhood says, he will do anything to protect her.
 * Threaten his little brother Al while Ed's around and you'll find yourself very, very, VERY soon regretting it.
 * It's also not too much of a good idea to bring up memories of the human transmutation incident for laughs, although this was more of a Tranquil Fury in the first episode of Brotherhood.

"Roy: *literally growling, eyes on fire* Stand aside, Lieutenant...there's going to be a fire tonight."
 * The closest Ed ever comes to killing someone is when he has up against a wall after Ed realizes he  He might have let him go if  hadn't decided to show us all what a bad idea it is to laugh at Ed's worst memory. He was on the road to getting pummeled to death with a steel fist before Al pulled his brother off.
 * Winry Rockbell:
 * Edward finds himself the victim of her Berserk Button whenever he needs to go back to Winry for maintenance and (predominantly) repairs. If there's even so much as one scratch...
 * Also, never criticize her handiwork. After hearing someone insult her automatic craftsmanship in the first anime, Winry went from telling Ed to calm down to telling Al to let Ed go so he could (more or less) kick the guy's ass.
 * Roy Mustang:
 * Much like Ed with Winry, it is a very bad idea to even imply that you might harm Riza Hawkeye. Your only chance of surviving such an implication is if he is heavily restrained.
 * Don't imply that you're attracted to her, either. In the manga, Barry the Chopper declares that he's in love with Riza (because she shot at him instead of screaming in terror). Then he makes the mistake of putting his hand on her waist, clearly against her wishes, in front of Roy.


 * Oh, and don't suggest that she really enjoys killing, like Kimbley did when they were all serving in Ishbal. Riza in a Corner of Woe makes for one really pissed-off Roy.
 * Roy is generally a Chessmaster who pretends that he is only concerned with pursuing career advancements and chasing girls shamelessly. But if you dare to harm his comrades, he'll give you hell for all he's worth. Literally.
 * Chapter 93 of the manga shows that mocking the death of Roy's close friend, is another excellent way to push it.
 * Izumi Curtis
 * Izumi seems to have a few of these, and they seem to be set on a hair trigger. Don't call her old.
 * Or hit on her when her husband is around. Just because he's a Gentle Giant doesn't mean he can't beat you to a pulp when provoked.
 * Try to abduct Izumi's apprentices. No, really. Go on. Try. But better have your will signed first.
 * Other characters:
 * You shouldn't tell Hawkeye that you killed Mustang (even if it's not true). The result is not pretty.
 * A scene with Greed in the manga shows that calling Envy "ugly" is a great way to tick him off, and get him to turn into his true form to kill you.
 * In the first anime, mentioning is a great way to have your face pounded in by Envy.
 * Don't threaten or try to kill the first anime version of Sloth. Wrath will go fucking BERSERK on your ass.
 * Not that they really need it, but messing with the Briggs Bears will earn you the immediate, violent wrath of Olivier Milla Armstrong.
 * Gluttony is usually a Psychopathic Manchild who just doesn't get that eating people isn't very nice, but hurt his beloved Lust and watch him completely flip out.
 * Scar does not take well to anyone involved in the Ishbalan genocide. And "does not take well" means "will dissolve your head via Face Palm of Doom."
 * Ed and Al share a minor (in Al's case, not so minor for quite a while) one that is labeled "Pointing out how GREAT it actually is being a soul trapped in a suit of armor". It led to one pretty not-so-nice brother fight.
 * Don't mock Hohenheim's sons in front of him. Just...don't.
 * Any open or implied disrespect of Ling in front of his vassal Lan Fan will result in her giving a Death Glare to the person responsible, at the very least, or her attacking the offender.
 * Ling gets pretty pissed whenever someone, especially those in positions of power such as, try to convince him that leaders should be able to abandon their followers.
 * Do not mess with Greed's "possessions".
 * Lan Fan doesn't take kindly to people insulting Ling.