TV-Head Shout Guy (a.k.a. "The Director") from Mondo Medicals. "DO YOU KNOW WHAT A CANCER IS?" Made even WORSE by the fact that his spoken "language" sounds like the result of asking a really bad voice synthesizer to say "thjedhg!!2@#@." At maximum volume.
Kratos from the God of War series. Though he is a man of few words, when he actually speaks he does so in such a powerful, loud voice that all of Greece can probably hear him threatening the gods with bloody death. Then again, given the size of the opponents he fights (the Colossus of Rhodes, the Hydra, he's communicated on several occasions with Titans), maybe he's just trying to make sure they don't have to strain to hear him. Regardless, Kratos can out-shout even Leonidas any day. Must be something about those Spartans... Add to that his overly dramatic dialogue and inflection and it can sound almost cheesy.
"CRY SOME MORE!!!" "HEY BOYS IT'S A SPAH!" "THIS IS MY WORLD, YOU ARE NOT WELCOME IN MY WORLD!" "THAT'S THE WAY Y'DO IT!" "GO ON, RAGE QUIT, MAKE US BOTH HAPPY!" "I AM FULLY CHARGED!" "JAA-RATE!" The only class that doesn't yell is Spy since he's supposed to be stealthy. Pyro yells, but you can't understand a word anyway.
(Pyro lifts flame thrower over his head) "MMMMPH! MMMMMMMMMMMMPH!" "I AM BOOLITPROOOOOOOOOF"
Heck, even the Spy yells occasionally. Upon hit with Jarate: "What is this...MON DIEU!" and "I HAVE BEEN SHOWN WHO IS THE BOSS!". Upon Dominating a Medic: Laughter really is the best medicine! AHAHAHAHAHAHAHAAA!
About half of the Sniper's lines are whispered, which makes sense since he wouldn't want to alert potential targets while scoped in. When he dominates his enemies, though, he goes into full-on Large Ham mode.
In F.E.A.R. 2: Project Origin, Colonel Richard Vanek does not talk quietly. Even when he's talking in a "normal" tone, he's practically yelling at the top of his lungs. This is typically punctuated by lots of swearing.
Some of the more animalistic demons in Shin Megami Tensei games speak in all caps when they speak.
Beast Demons: FEEL THE CALL OF NATURE.
In Persona 3, Some of the Personas upon being fused have a case of this, with their dialogue being written entirely in capital letters.
Captain Cid in Final Fantasy X has just two kinds of speaking: Shouting and yelling.
Also Fujin from Final Fantasy VIII. She speaks explicitly in ALL CAPS. And few words. For example, rather than ask "Where is Ellone?" she says "ELLONE. WHERE?" It was actually meant to translate the fact that in the original Japanese version, her speech is entirely in Sino-Japanese ideographs (i.e. no phonetic hiragana/katakana at all, which is very unusual for ordinary Japanese speech and writing). From the same game, NORG also speaks in all caps, though unlike Fujin, he does so in complete sentences, and even his name is always written in all caps.
Doctor N. Gin in the Radical Entertainment Crash Bandicoot games. That is all.
"Still... no... SLIPPERS?!?!" "THANK YOU AGAIN!!! Hotter than the first!!" "NOT MY THROAT!! I need that for swallowing!! GUARDS!!"
Blue Dragon gives us Marumaro, whose combination of no volume control, screeching virtually all of the time, and a oddly disturbing crush on Zola makes him The Scrappy to many fans. And even if he's not, they usually agree on his voice.
THIS is LOUDRED'S Verbal TIC. He ALTERNATES between SCREAMING ALL THE TIME and JUST emphasizing random WORDS. OH, and the FLAT OUT SCREAMING tends to HAPPEN when he WAKES YOU UP EVERY MORNING.
Palkia LIKES TO TALK IN ALL CAPS IN A COMPLETELY SERIOUS, ANGRY, ENRAGED, IMPATIENT TONE. ALL THE TIME. HE TALKS MORE LOUDLY MORE OFTEN THAN LOUDRED!!! DIALGA DOES TOO, BUT HE HAS LESS DIALOGUE THAN PALKIA!!! IN CASE YOU HADN'T FIGURED IT OUT, PALKIA AND DIALGA HAVE LOUD, BOOMING VOICES. AND DIALGA HAS RANDOM ROARS IN THE MIDDLE OF HIS DIALOGUE.
In the Japanese version of the game, however, they simply speak in an archaic dialect to give off an ancient and powerful vibe instead of abusing exclamation marks.
Magnemite also has no indoor voice, which may be justified because they're rather machine-like.
Inverted with boss dialogues which are shown as "X yells Y," yet the actual audio files are (generally) spoken at a normal level.
Played straight just as often, however, with many bosses and NPCs relentlessly roaring their dialogue at the top of their lungs.
In Pokémon X and Y, Essentia's dialogue is written in all caps. It's hard tell if she's yelling or if it's just to point out that her helmet is digitizing her voice.
In Pokémon Omega Ruby and Alpha Sapphire, while she doesn't speak in all caps, Flannery's angry, open-mouthed expressions and her explosive speech bubbles seems to suggest that she's yelling at your face in order to seem impressive.
EVERY CHARACTER IN CHRONO CROSS HAS A PERSONAL VERBAL TIC. ZOAH'S IS TO SPEAK IN ALL CAPS ALL THE TIME LIKE THIS AND FANS TEND TO INTERPRET IT AS HIM YELLING CONSTANTLY.
Steven from Dead Rising would like to remind you all that THIS IS HIS STOOOOORE!.
In the Telltale Sam & Max: Freelance Police games, Bluster Blaster of the C.O.P.S. shouts all of his dialogue in a manner resembling Sinistar(except in Episode 203: Night of the Raving Dead, where an accident has considerably quieted him).
In Mega Man Legends, Teisel Bonne has three tones of voice: normal, YELLING, and SCREAMING. The latter two are his most oft-used tones of voice.
Teisel Bonne: I said CLOSE THE HATCH!
Ishut, protagonist of Gloria Union, is like this; he's very enthusiastic and has the maturity level of a six-year-old. His allies (and even his voice actor!) find it extremely annoying. The Japanese fanbase has declared him a Fountain of Memes.
Planescape: Torment has Coaxmetal, a geant golem (sadly not voiced) that speaks in all-caps. It pales however in comparison with The Transcendent One, voiced by Tony Jayathisverybest. All of it lines are also in all-caps.
The Transcendent One: "I CAN FORGE PLANES WITH MY POWER. I CAN UNMAKE YOU."
In Prince of Persia: The Sands of Time, we have the British soldier guy who is yelling to the character across a room on how to complete a puzzle involving moon segments and rotating platforms. He constantly yells things like "THAT'S IT!" and "ONE MORE TO GO!"
Neverwinter Nights 2: Male, Brooding Dark Hero. His volume range goes from Loud to Really Really Loud. Hell, even his call to the group to be quiet is loud!
Messenger Sparks from Armed and Dangerous. This is either a cause or an effect of his near-deafness, which leads to Hilarity Ensues when he's forced to conduct negotiations between the Evil Overlord and the noble bandits who have 'kidnapped' his son.
MR. TORGUE never does ANYTHING by half-measures, and APPARENTLY that includes TALKING!
Salvador. Just listen when he laughs at the carnage you cause or when starts Gunzerking.
Salvador: TIME TO OVERCOMPENSAAAAAAAAAATE!
Krieg, being a psycho, alternates between this and his inner voice quietly commenting on the insanity.
"I'M THE CONDUCTOR OF THE POOP TRAIN!!!"
THE OFFICIAL BLOODCRUSHER II DEVELOPMENT TWITTER ACCOUNT IS ALL CAPS, ALL THE TIME.
The Reality-On-The-Norm series has Mr. Namyah, the Sadist Teacher of P.E. His sole mode of speech is cartoonishly screaming his lungs out in all caps, no matter what the situation.
In the entirety of Warhammer 40,000 media—games, books, everything—the orks are characterized as loud, boisterous Blood Knights with No Indoor Voice. Warboss Grimskull of Warhammer 40,000: Space Marine is of course the same...with one exception. He's thrown down a Bottomless Pit with a bunch of daemons, only to return a few minutes later with the only quiet line from an ork in Warhammer history.