Crisis Equestria/YMMV

"Rainbow Dash: "Aww, you guys are cute together.""
 * Complete Monster: Shadowstep, full stop. Sadistic murderer who takes pleasure not only in killing, but doing so in amusing ways and at particularly evil moments. Silvertongue employs him as his personal assassin for specifically this reason, though it's clear that sometimes Shadowstep's enjoyment of his killing gets in the way of actually killing. He is appropriately punished for this, but as Tick Tock soon learns,.
 * Foe Yay: Invoked by Tick Tock, who taunts Starlight Shadow's attempts to frighten Twilight's group into submission by a display of power, as her basically showing off in an attempt to flirt with her. Starlight Shadow never specifically denies any sort of attraction to Tick Tock, and the 'Chronomancer' title she calls her by, eschewing her real name, can be taken as a bit of a pet name for her. Shadowstep is the only other character that knows Tick Tock's name yet still calls her Chronomancer to her face, hinting that perhaps he too falls under this trope. Silvertongue is excluded, as he only refers to her title when referring to her and talking to others, and the two have never interacted personally.
 * Ho Yay: Despite their status as Heterosexual Life Partners, Flathoof and Lockwood definitely have shades of this, none more blatant than in Chapter 12, when the party is stuck in a cramped space and Lockwood has apparently been rubbing Flathoof's flank, thinking it one of the mares in the bubble. When Flathoof tells him off, Lockwood doesn't outright show disgust, but actually compliments Flathoof on his toned flank. Rainbow doesn't miss the opportunity to call attention to it.


 * Incest Yay Shipping: There is an awful lot of subtext between Starlight Shadow and Silvertongue, who she knows as her adoptive father. She seeks to please him by carrying out his orders flawlessly, takes great pride in being his favorite, and emulates his way of speaking (though hers is a little off). He, in the meantime, adores her for her incredible power and loyalty to him and regularly makes point in front of the others that she is his favorite.
 * Curaçao and Insipid don't count, as their budding relationship is fairly out in the open.
 * Jerkass Woobie: Tick Tock is a jerk, and she may have a heart of gold, she's still rather a jerk in general. Despite this, she deals with significantly more punishment than any other single character in Twilight's party, nearly getting killed over half a dozen times on her own by now, and getting traumatized when she finds out that Shadowstep  Her relief that he can't follow her is hers alone - the readers know he can, and is.
 * Nightmare Fuel:
 * Red Velvet's techniques for frightening ponies may or may not actually be frightening to the reader. Chapter 24 so far is the pinnacle of her power, and she becomes so strong as to actually corrupt the text.
 * If one has a fear of insects, the Gargantuans are of course likely this for you.