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Nightmare Fuel: Marvel Avengers Alliance
Where do we start... This game is PG-friendly and simply-rendered, of course, as a simple Facebook game designed for universal appeal. But perhaps some parts of it are better left merely implied.
Loki has a disturbingly cavalier line right before his boss fight.
Loki: The heavens have bestowed a gift on this planet, and I intend to take it. After I take your head, of course.
The Brotherhood and the Hellfire Club infusing unwilling regular humans with Mutant Growth Hormone-tainted ISO8 to create mutants, who are often driven crazy and resemble disfigured lab test subjects more than people.
Even better, one of them has a Meltdown attack which basically involves blowing himself up to harm everyone on both sides. Yes, that's right, someone is mind-controlled into being a suicide bomber.
Can you imagine the horror of it all if Mystique's plan to forcibly mutate everyone in Manhattan had succeeded?
On the anti-mutant side, you have what happened to Omega Sentinel.
I discovered that I was a Prime Sentinel as well. That's when the programming dropped over me like a shroud, and I lost myself. Only now do I realize what was done to me. My bones and muscles were torn from me, replaced with carbonized titanium and reactive polymer. They filled me with plasma weapons, blades, bombs, disruptors, and sensors. So many sensors.
The sheer number of disposable Mooks that you and your team plow through gets pretty depressing after a while. The enemy leaders seem to have an infinite number of ninjas/gangsters/escaped prisoners/HYDRA soldiers whose sole gameplay purpose is to be cannon fodder.
Abomination eating his own allies to gain power. Epic Overkill, indeed.
Besides the assorted humans and mutants you fight through the story's course, how about Frost Giants, Mindless Ones, the odd Eldritch Abomination like Dormammu, demons and even lords of hell?
Not to mention demonic portals opening and hell creatures escaping into New York, as well as the battle background with skeletons all over as you traverse towards the edge of hell...
Subcinctus or Meretrix succubi look like a not-unpleasant cross between a woman and a fuzzy scorpion — until one of them uses her Hell Hath No Fury counterattack. She falls to her knees, and then a giant alien crab insect thing comes out of her back and hits your whole party with a beam from one of its many eyes For Massive Damage.
Mephisto claiming his Contractual Obligation from allies who have Sold Souls, by killing them and draining all their life force into himself.
The attack Where the Sun Don't Shine jamming a bat right into some rather sensitive parts and causing bleeding.
The Mindless Ones with their Abyssal Stare, which eats up half your health each round unless you heal it. The sort of spirit-draining terror this affliction might have is best left unsaid.
Even your roster of heroes can bring the nightmare fuel.
Magik has a move called Soulflare where she opens her mouth wide and has a giant beam of white energy come spewing out to hit an enemy, not to mention her various creepy one-eyed demons and summoning a piece of Hell to Earth. She's pretty much a Creepy Child herself.
Ghost Rider, he with the burning skull head, has hellish imagery swirl about when he activates his Penance Stare.
The animation being, the Rider's flaming visage facing you.
Black Panther summons the Panther spirit to enter Panther Stance. The ghostly, snarling Panther head that suddenly appears over him is unsettling the first time you see it.
Some of the debuffs would be pretty nasty to have in real life - Soulfire, Creeping Petrification and Rapid Psychosis come to mind.
Some of the Mooks can fire phosphor rounds as their ammo, which inflict burning. "Ow" doesn't quite cover it.
And now, with the Phosphorus Pang, you can fire phosphor rounds as well. Can you say Mook Horror Show?
The "Bleeding" status effect received a most unwelcome buff which causes heroes to take "Bleed Out" damage. Before, Bleeding could stack up to five times and caused damage at the beginning of each turn but it was a relatively light loss of HP and could be safely ignored. Now, it can stack only three times, but damage is taken at the start of the turn and after every offensive action. Add to that the visual red 'splatter' on a bleeding character as s/he takes damage and this game becomes highly disturbing for anyone who is Afraid of Blood.
And it gets worse. Some attacks inflict Ravaged (increases bleed damage) and others are Hemorrhaging attacks (cause massive damage depending on how many stacks of bleed the victim has). In short? Bleeding is now right up there with Dark Void as a status effect which can kill an entire team. The damage is so terrifying that Bleed is one of the many debuffs you'll want to patch up fast.
And if all that were not bad enough, Elektra (and perhaps others) can inflict an "Internal Bleeding" debuff which causes the same damage, lasts several rounds, can stack, and cannot be cured on the field.
All the revival shenanigans using magic/science/ISO-8 in the later chapters of the story are especially creepy, especially when Daredevil reports that he's witnessed The Hood ritually murdered and then resurrected. Doubly so when it involves the long-dead corpse of the Red Skull.
X-23 probably doesn't just scare others, but herself as well. Her Weapon X Programming passive can give attackers a Trigger Scent, which forces her to attack them. Additionally, the longer combat drags on, the more Enraged and lusted with Berserker Rage she is likely to be. Berserker Rage also grants her a chance of added attacks against bleeding targets. Imagine this beautiful young woman, whose struggle against her dark past and nature is a big part of her story, going involuntarily out of control with rage and repeatedly Snikt!ing the battlefield with bloodied claws when she catches whiff of the Trigger Scent, possibly even killing off opponents for good with Assassin's Strike.
To clarify — if a target has the Trigger Scent, she can't attack anyone else. She has to attack that particular enemy, even if it would be better not to (e.g. an Infiltrator with Combat Reflexes). The player has to decide whether the possibility of injury to X-23 outweighs the extra damage she will do to her target.
It gets worse — the player can choose whether to attack only the enemy marked with the Trigger Scent, or they can use X-23's Blades of Rage ability to attack all enemies at once. If they go with the latter option, there's a chance that X-23 will go into a Berserker Rage and hand out follow-up attacks to everyone who's bleeding (i.e. everyone who didn't dodge the Blades of Rage). If this happens, this one little girl can wipe out just about everyone on screen without the player really trying.
It gets even worse with Mission 2.5.2's Heroic Battle. HYDRA seeds the area with Trigger Scent, forcing Kitty Pryde to take on the berserking X-23. If you can last the 9 rounds until the Trigger Scent wears off, X-23 comes to her senses, but the dialogue reveals that Kitty is badly wounded, enough to require immediate medical attention. Imagine X-23's horror as she realizes she has nearly brutally killed her friend, with absolutely no control over her actions.
One of the deploys in Season 2 has Shatterstar investigating a monster that has emerged from another dimension. The description of it, including "Some creature from another dimension is slithering around this area" and Shatterstar saying he "cut off its heads, then [he] killed what emerged from the wounds," and that they should "burn the remains", makes one wonder just what sort of abomination the creature was.
The completely matter-of-fact way that Shatterstar says this makes it all worse, somehow.
The whole Spec Ops 12 scenario of having certified psychopaths like Dell Rusk (a.k.a. Red Skull), X-Ray and Bullseye manage domestic security is deeply unsettling, to say the least.
Imagine an alien invasion like the Black Order's in Spec Ops 13, presenting you with 2 choices: either slaughtering all the young men in New York City, or slaughtering everyone in the city if you choose not to do the first...
As someone who was primarily focused on healing, Thane's newfound Touch of Death must have been pretty horrifying when it first manifested and he had no control over it.
"An anomaly in your user data has been detected. A negative effect on PVP may be taking place. If you are using third party software to manipulate Avengers Alliance data, please turn them off. Further attempts at data manipulation will result in a ban from PVP."
There are three things that make this Nightmare Fuel for innocent players receiving this message. One, for the simple fact that they're being accused of something they didn't do; Two, the opening line makes it sound like their account has been hacked, and Three, if you're a "Wallet Warrior" who spent any amount of cash on the game, this comes across as your money being taken from you for a crime you didn't commit.
In the latest special ops Black Cat mentions catching Scream (a symbiote, one of Venom's offspring) attempting to get into a daycare.
The Sugar Man and his boss fight, a horribly mutated... thing that can get extra attacks every turn and has attacks that involve licking the player characters.
The Circle of Eight's off-screen massacre of various Marvel characters throughout Season 2. Eight are murdered per chapter, which are tribute to call forth one of the Eight Hammers of the Worthy. That will be SIXTY-FOUR ritual killings in total.