Ponies of Dark Water

Ponies of Dark Water is the fifteenth story arc of IDW Publishing's, spanning issues #43 through #45. In the story, the Mane Six become evil after being exposed to a newly discovered hot spring, and it's up to Spike, Princess Luna, and the Cutie Mark Crusaders to save them.

Issue #43
On their way home after saving Equestria from a threat in the kingdom of Abyssinia, Twilight Sparkle and her friends come across a newly erupted hot spring. According to Fluttershy's butterfly friends, the springs just appeared in the last couple of days and have caused a commotion among the wildlife. After their most recent adventure, the ponies—not including Spike—decide to relax for a while in the hot springs before returning home.

The next morning, Spike awakens to find Ponyville in a mild panic; Rainbow Dash has been performing one sonic rainboom after another. Even more bizarrely, Applejack appears and sternly addresses Apple Bloom like an employee instead of a sister, Twilight makes a public announcement declaring herself empress of Ponyville and promising a harsh but fair rule, and Rarity walks around town wearing a cloak and iron mask.

Spike and Apple Bloom assemble the other Cutie Mark Crusaders at the Crusaders' clubhouse, and Spike explains that his friends' strange behavior started after relaxing in the new hot springs near Abyssinia. In addition, Fluttershy and Pinkie Pie have mysteriously gone missing. Spike sends a letter to Princess Celestia informing her of the situation, and Celestia entrusts it to her sister Princess Luna because of her personal experience with dark forces.

Back at Sweet Apple Acres, Applejack tries to demolish the Crusaders' clubhouse under enforced eminent domain. Before she can put Spike and the Crusaders to work to pay off months of back rent, Princess Luna arrives to investigate. She seizes Applejack and tries to extract the dark magic inside her, but Applejack breaks free and escapes. Luna explains that whatever magic has a hold over Applejack is making her more powerful.

After Spike and the Crusaders explain to Luna what has happened to the Mane Six, Luna tells the Crusaders to find Zecora while she and Spike contain the damage in Ponyville. However, on their way into the Everfree Forest, the Crusaders run into Fluttershy and her animal minions. Meanwhile, at Sugarcube Corner, Pinkie Pie puts on clown makeup while laughing maniacally.

Quotes

 * Twilight Sparkle: Well, we've saved Equestria once again.
 * Applejack: And good news is this time they're aren't going to prosecute.
 * Rarity: The kingdom of Abyssinia is strangely litigious.


 * Applejack: What the gold-durned ding dang is all this?!
 * Apple Bloom: One of those rainbooms knocked over the cart. I'm okay, though.
 * Applejack: I ain't worried about you! I'm worried about my apples! Do you know many sales you've lost?


 * Twilight Sparkle: I, Twilight Sparkle, am appointing myself empress of Ponyville. As the most intelligent pony in this town, or any other, it is the only logical course of action.


 * Rarity: The arrogance of that pony, thinking that she can rule Ponyville. When it should be me. There's no one finer, or with finer finery.


 * Spike: They were normal the whole trip back. We even took a break at those new hot springs.
 * Sweetie Belle: New?
 * Scootaloo: Hot?
 * Apple Bloom: Springs?
 * Spike: When you put it like that, it sounds kind of obvious.


 * Princess Luna: My history is one with its own darkness.
 * Princess Celestia: Precisely. Whatever has happened here, you have personal experience, tragic though it may be, with such forces. I can think of no one else better for the task.


 * Scootaloo: At least Pinkie Pie and Fluttershy haven't caused any problems.
 * Sweetie Belle: That we know of!
 * Scootaloo: Take that back! You'll jinx it!


 * Fluttershy: We appear to have—intruders.


 * Pinkie Pie: Heh hehehe ha—ha ha hahahahah ahaha! Wait 'til they get a load of me! Hah ha hah hahahah!