Duane Mellor, from "Eater", is a Cajun murderer and "Eater" who was arrested for torturing, murdering and eating vast amounts of innocent people, often keeping them alive for days so he could cut pieces off and eat them. Once captured, Mellor waits until the graveyard shift before using a voodoo ritual, devouring the souls of several officers with their hearts to take their forms and play a sadistic game of cat and mouse with the young female rookie cop on duty, solely because he enjoyed frightening his targets. When his patience is exhausted, Mellor simply goes for the kill.
Forest J. Caldwell, aka the Beast Killer, from "Something with Bite", is a man obsessed with werewolves and becoming one, and stands in stark contrast with the benevolent werewolves seen in this episode. Donning a makeshift werewolf outfit, he goes around killing multiple people across the city in a manner which is mistaken as animal attacks; this is all to attract the attention of real werewolves and fulfill his dream of becoming one. In one instance, he mauls Kayla, a friend of such a werewolf named Wilbur, but is unable to kill her when he's scared off by police. When Wilbur confronts him, Caldwell questions if he's upset about Kayla, stating he intends to finish her off at the hospital.
Faux Symbolism: As it's primarily set in a church, "In Sickness And In Health" naturally has a lot of this.
Idiot Plot: "Chance". Everything the characters do is stupid.
The plot is set into motion when the titular Chance (later revealed to be not just stupid but also insane) falls for an obvious Ponzi scheme that requires him to invest $20000 in a Chinese vase under the promise that he can sell it for $45000.
When an antique dealer offers him only $5000, he leaves without taking the vase or the money.
The smoke sets off a fire alarm. Chance destroys it. A security guard calls the store and Chance answers the phone. He fails to deliver the security password required and the guard goes to the shop.
Despite being already night, the light out, the shop closed and the owner nowhere to be seen, the guard sort of buys that this guy that doesn't know where the switches are or what the password is is a new employee in his first day in the shop, and doesn't react until he discovers the dealer's body.
Chance kills him and also stays to clean the mess. The phone rings again and he answers it again. It's the dealer's wife that is waiting for him because they were supposed to start a minivacation that night and he's getting late. He pretends to be the dealer and she comes to the shop.
Not finding her husband, the woman... uh... takes a shower? In the shop? Oh, and Chance kills her too.
And so Chance goes back home with no money and since he has already killed three people, well, he kills his wife too while he is at it, and waits for the police to apprehend him. The end.
Nightmare Fuel: The last scene of "In Sickness and in Health" is perhaps the creepiest part of the episode, especially since Maggie Lawson did such a good job.
What an Idiot!: The writer in "The Circle" tells the girls to make light by setting the furniture on fire. Keep in mind they are in a locked room in a wooden cabin with no way of putting proposed fire out.
Big-Lipped Alligator Moment: Spider-Man randomly leaves to check on Aunt May. This is likely to set up some time for tie-in issues to take place, but it adds almost nothing to the story and various characters call out Cap for sending him off. It's not like we see Dr. Strange check up on Wong.
Like You Would Really Do It: While most people were pretty sure Thor was/would be dead (the previews for future comics even showed his replacement), he's too big to stay out of the picture for long. And indeed, a few months later Thor was back with the living again.
Replacement Scrappy: Tanarus, the guy supposed to replace Thor after this event was already hated by the time he appeared, because he looks like a '90s Anti-Hero, his appearance and Thor's death mean that there won't be interaction between Thor and Kid!Loki for awhile, he's not using Mjolnir at all, but a weird staff with a heavy head (indicating to fans that he's not worthy to be Thor anyways, since a worthy person can lift the hammer), and for not being one of the many established people who could take over for Thor, namely Beta-Ray Bill and Thunderstrike. As Kid!Loki immediately realizes something is wrong with Tanarus and that Tanarus turns out to be Thor's old enemy Ulik in disguise, this was surely intended.
Tearjerker: Tony, furious with Odin, yells that if they're gods, then he'll sacrifice the only thing he can give that's worth anything... and takes a big swig of alcohol... And after so long being clean, too. Later issues of Fractions's Invincible Iron Man imply that this was in part a Senseless Sacrifice, and that Tony, faced with the end of the world, saw an excuse to give in to his addiction.