Hammer's apparent death while trying to escape the Ellie Arroway, as well as the revelation of an apparently devastating plan by the colonial rebels
In the last battle of the first part, Loser being accidentally killed by Whiskey, Corona Squad being all but annihilated in seconds, Hammer being revealed as alive, Bubblegum leaving the ship with Toat, and the Icebreaker squad being disbanded.
In Arthur, King of Time and Space, there was a Wham Episode before the first Time Skip, with Merlin's death in the MASH and Contemporary arcs. Before the second Time Skip, there was a Wham week. Mark kills Tristram and Isolde in the baseline arc! And the space arc! And the Western arc! And then in the contemporary arc, where there hadn't been any violence previously! And then the heavily foreshadowed Karmic Death of the semi-evil False Guenevere is mirrored with the Unkarmic Death of her not-at-all-evil contemporary counterpart Fasha.
After the second Time Skip, we open with a Wham Episode, although in this case a positive one. You thought Arthur's role as CEO of Excalicorp was the equivilent of being High King? Nope, he's standing for President.
'Bittersweet Candy Bowl': Chapter 51, where Lucy finally works up the courage to tell Mike she loves him... only for him to reject her on account of him already having a girlfriend. Possibly WORSE is Chapter 52, where Mike finally gets sick of Lucy's awful behavior towards him, leaving her nearly broken inside. Keep in mind that nearly the entire comic had been built upon Mike's friendship with Lucy, and his willingness to look past her attitude to see who she really was. Yeah. WHAM.
Castlevania RPG has had two, one played for comedy, the other for grimness.
The comedic one: Blacula escapes his prison and turns Succubus against Team Dracula, then takes over Castlevania. The comedy comes with the general shenenigans of the cast still applying in what is otherwise a kinda serious scene.
The dead-serious one; While exploring some ruins while in a parallel world, the team accidentally releases an Elder God, which is just as pleasant as it sounds. In the space of only a few comics, the God brutally murders Alec and Katrina's magic chooses the absolute worst moment to go completely haywire, causing her to accidentally kill Princess. This leads to her Cat Girl curse turning her fully cat, and Angel specifically states that there's literally nothing anyone could do for her now. And to top things off, the Elder God possesses Angel. The chapter ends with Elder God=/=Angel grimly telling Darkmoon that there's nothing he can do to stop it, that everything he and the party did was ultimately pointless and ineffectual, and then calmly obliterating him. Thankfully, Darkmoon turns out to be Not Quite Dead, and manages to save the day through Playing Chess With Death and Time Travel.
Cheap Thrills - Chapter 3: Jeordie is goes on a Mushroom Samba after taking spiked mushrooms. It looks like a round of "Jeordie's stupidity earns him another hard life lesson" and Jeordie's mom Elizabeth goes on the errand Jeordie was now incapable of, sharing a bonding moment with younger son Faris in the process. but that gets turned on its head when Elisabeth and Faris are killed when a semi drifts into their lane and hits them head-on.
College Roomies from Hell: Mike finally hatefucks gives in to April's advances, then brutally rejects her afterwards. April responds to this Marsha playing "pretend I'm going to slit April's throat" by running Mike through with a large knife, killing him. Arguably marks the point where CRFH hits full-on Cerebus Syndrome territory.
You missed the motivation for that event. Satan was taking advantage of the deal Mike made during his short stay in hell. Mike agreed to give Satan 15 minutes in his body to protect Marsha.
Not only that, but some of the 2009 strips imply that Mike is actually the Archangel Michael, sent to protect the earth.
Digger manages a fair few. The first that the Cold Servants are Hyenas came as no surprise to most as the nature of the dead god had been so heavily foreshadowed if they turned out to be anything else people would have objected. However Ed being Grim-Eye's father although foreshadowed was foreshadowed so subtly it came out of fricking no-where as far as most readers were concerned, but makes so much sense in hindsight and is such a heartbreaking revelation it jumps right off the HSQ metre.
Almost the entirety of the Shadow of Siegfried arc, but ''this'' one in particular, showing why Siegfried wound up in hell.
Fourinagoddamnedrow in 8-Bit Theater. The third one is, arguably, the whammiest because Fighter, for the first time in the comics 1,000+ , seven year run, has actually shown anything but admiration and love towards Black Mage; and Black Mage, for the second or third time, has shown genuine affection for White Mage.
And all three of them paling beside the revelation that Sarda is actually the Onion Kid, out for revenge against them for Black Mage mind raping him and killing his foster parents. Repeatedly.
You have to admit that the fourth one was really whammy because Black Mage actually killed Fighter. Granted, he's been threatening to do that for years, but he actually succeeded in doing it this time.
Ya, for all of a minute.
Also, the defeat of the Big Bad in Episode 1221; which was lampshaded in Episode 7; a wham with a set-up spanning the entire series.
Word Of God: I have frequently seen Susan described as having a "bored" look on her face. For a long time now, I have seen it as something else.
Erfworld: Depending on how far you took the "world with game-like qualities" thing, when we find out that people literally pop into existence, fully formed in cities, you might be hit as hard as Parson was.
Erfworld is liberally sprinkled with these, which makes it incredibly hard to predict where the story is going.
Back to Back wham's Bogroll kills Ansom, and then dies and Parson has Sizemore and Wanda ''uncroak the extinct volcano that Gobwin Knob is on top of wiping out most of Ansom's forces
Everyday Heroes has this literally when Jane Mighty (in her old life as "Iron Jane") discovered the truth about her team leader, Wrecking Paul: he was a serial killer who murdered her best friend right in front of her.
It's Walky! (back when it was still Roomies!) had Ruth die saving a drunk Danny from getting smashed by a semi. Prior to this, the strip was pure drama-free Sitcom. The shift in tone may have been 100% intentional, since the storyline immediately following that shifted the strip fully to It's Walky!.
Perhaps special note goes to strip 394 where Liquid has to murder a likable hacker attached to his team in order to keep a secret. As the author himself posted on the news page when the comic first came out "Shit just got real".
Last Res0rt, Episode 3: during the assault on the White Diamond Crisis — after being lured deep enough into the ship that Gabriel is able to Tone the majority of the players into stupefied submission, it's up to the remaining unaffected players to save the day. Jigsaw and Daisy manage to recover most of the others, but Daisy's 'snapbacks' backfire, first on Cypress (who dives into a pool full of aggressive nanotech), and then after that problem gets solved, it happens again on Jason, who mortally wounds her! After all of this, GEISHA figures out a way to save them... but Gabriel's forces arrive just in time to capture the remaining vulnerable players before they can be ferried back. OUCH.
The 2nd to last comic of Chapter 9 in Megatokyo where Ed uses an army of Killballs to Combination Attack Miho, apparently killing her. The entire thing needed the 1st 2-page comic to be shown.
After 1,000 pages of generally good progress on a resolution in Misfile it's finally revealed how long it will take Rumisiel to get back into heaven and fix things in this strip. 72 years.
To say nothing of the revelation that the titular filing accident is literally the only reason Emily is still alive.
Mob Ties: Once you reach Issue 7, Revelations, be ready for a Wham Episode every Issue, because once it's revealed that Mika was the victim of a violent rape so traumatic that it has left her severely traumatized to the point that she cannot remember it and passes out when anyone mentions it to her, the plot kicks into high gear.
And the Whams become even bigger when Issue 14 rolls around, and the Big Bad Bengal appears.
And one now in progress with Faye and Angus starting here. This moment signifies how greatly she has turned around and matured emotionally more as a person after her father's suicide and her lustful tryst with cheating Sven to relax and risk going out on a date with Angus. Bonus points for that surprise kiss from Angus being an Meaningful Echo on how Faye surprised her previous lover Sven with both men talking with Faye how the unexpected can be a good thing.
Add another one to the pile. #1799. "It's been wonderful, sweetie. It really has. But I think we should call it quits."
Scary Go Round has a Wham Episode during the second Super Crisis Quests storyline when we learn that the character previously thought have been to be the Devil was just a character actor named Old Nobby, and the Devil was revealed to actually be crazy old Ralph after Nobby's death.
Shades, Chapter 10: the bad guys get parliament suspended and put a puppet in charge of the UK.
Something Positive gave us a wham in the "Just Today" story, where Fred and Faye spend a day together, and Fred struggles on how to tell her he has Alzheimer's. He decides to wait until tomorrow, which is where the wham comes in: Faye dies in her sleep overnight.
Issue Ten of the infamous Sonichu, in which several of the main characters brutally murder a handful of people whom the author believes have wronged him in life. The childish aspect of the artwork could make it even more disturbing to some people.
The Super Fogeys first is when Dr. Rocket is revealed to be Herman, a shapeshifter the real Dr. Rocket used to try to ruin Captain Spectacular's reputation. Herman had reformed and was forced to become Dr. Rocket (the explanation how isn't so good), but after a blow on the head, this process broke down and more and more of Herman gradually begins to show. The reader's clue is when Dr. Rocket acquires a stutter, which Herman is shown to have in a flashback before the reveal.
This pales in comparison to the fact that the mysterious Dr. Klein and the Third Man are actually Jerry, Captain Spectacular's sidekick. The comic archives are FULL of subtle hints and clues — from the fact that Jerry is never seen in the same panel as Dr. Klein, to Klein's affection for Jerry and Spy Gal (Jerry is in love with the latter), to Jerry not having any powers yet was able to 'survive being thrown into a volcano' (the Third Man can appears to use a dimensional gate or can teleport), to similarities between designs, and the list goes on. Best of all, it is clear that this was planned from the very beginning.
Tales of the Questor: Old Secrets story arc: Quentyn's town learns to its horror that an old forgotten debt incurred by Quentyn's predecessor has grown until most of the town will be literally repossessed. Quentyn, up till now struggling as an underappreciated hero most of his town sneers at, volunteers to renew the original quest to cancel the debt and the series becomes an extended adventure of The Quest that makes him a hero of great honor in his community and beyond.
Terinu: Leeza confronts her father after discovering that Humanity knew about the Dominion using the Ferin as power sources and committed genocide against them to disable the Dominion. Then her father throws her in jail to keep her quiet.
This Is the Worst Idea You\'ve Ever Had! has the introduction of Jeremy's room-mate, Miguel...who happens to have the same character design as the villain from Cuanta Vida, Rojo. To some fans, this itself was a WHAM Episode. To others, the Wham episode would be the page after that, where Miguel reveals that he was the guy who committed the murder that had taken place earlier in the chapter, before starting to choke Jeremy.
As seen in the image at the top of the main page, VG Cats references this in a Lost Episode of Tom and Jerry, which is a deconstruction of the slapstick violence and Amusing Injuries the title duo suffer. Jerry is charged with aggravated assault, given a lengthy jail sentence, while Tom suffers irreparable brain damage and spends the rest of his life as an invalid.
What Birds Know: Page 431, which abruptly turns the story from a lighthearted fantasy romp through an Alternate Universe with a dark undercurrent into something really, really bad.
Yu+ Me: Dream does this in Issue 9, which was kinda unexpected (despite, you know, the title) due to the readers' emotional investment.
The MS Paint Adventures series Homestuck first seemed like a lighthearted Deconstruction of Sim-type games. Then the main character's house gets hit by a meteor, transported to The Medium, and we learn what the stakes of the game really are.
[S] Jade: Enter in its entirety. In order, Vriska puts John to sleep at a crucial moment, Bec prototypes himself in order to save Jade, then blows up the meteor heading towards her island (while unintentionally killing everybody else on Earth with the aftershock), Jade enters the medium, Jack Noir obtains Bec's powers and kills both Bro and Davesprite, it's revealed that the demon terrorizing the troll's session is Bec Noir, having crossed the universes through the Scratch, destroyed their versions of Derse and Prospit, and to top it all off, Jade sees snow for the first time. Phew!
Hey, you know the huge situation involving Bec Noir? Vriska planned ALL OF IT. Not just creating Bec Noir, but creating Bec himself. Oh, and Jade's Narcolepsy.
Holy balls. The second half of January 2011 qualifies, beginning with Tavros's death at the hands of Vriska, and continuing with Eridan's attack on Sollux, his murder of Feferi and Kanaya, and his destruction of Matriorb and the entire future of the troll race.Karkat's expression just about sums it up.