[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/antoncreepy.jpg]]
[[caption-width-right:350:Even BEFORE he becomes Mesogog, he's still terrifying.]]

* Mesogog, plain and simple. Possibly the most evil being since Lord Zedd.
** He's actually ''worse'', because Lord Zedd still had some sense of humor to him that made him seem more FauxAffablyEvil. Not with this guy, AT ALL! He's one of the few villains that didn't have an ounce of comic relief in him, or a softer side like Ransik's love for his daughter or Zedd's love for Rita Repulsa. (He [[LampshadeHanging lampshades this]] in "Back In Black" after a captured Tommy fires off another badass snark: "There's that wit again. If I had a sense of humor, I might actually appreciate it.") Never once during the entirety of ''Series/PowerRangersDinoThunder'' does he show the slightest traces of compassion and humanity (barring a single occasion where his human half intervenes on behalf of his adopted son - whom Mesogog himself is about to kill), and when his subordinates fail him, he doesn't throw a tantrum, he doesn't scream about how much of a headache he has - oh no, he tortures them via MindRape.
** Adding to his general creepiness is how well the facial prosthetics used for him work. Mesogog's suit looks ''extremely'' realistic, complete with a working mouth with internal details, makes him all the more terrifying.
** That monotone of his was scary as well: He never raised voice, not once. CreepyMonotone all the time.
*** The ''only'' time he raises his voice is when the Rangers discover his true identity.
*** He did get significantly crazier after he [[spoiler:separated himself from Anton Mercer]], however.
** What's scarier than Mesogog? Some of [[spoiler:Anton's]] ''transformations'' into Mesogog. No sparkly effects, just painful-looking BodyHorror.
** Upon trapping Lothor in a Jar: [[FridgeHorror "Very collectable".]]
* That [[BrokenAce Tommy]], after eleven years as a Ranger (active or otherwise) and five separate Ranger incarnations ([[Series/MightyMorphinPowerRangers Mighty Morphin Green & White]], [[Series/PowerRangersZeo Red Zeo]], [[Series/PowerRangersTurbo Red Turbo]], and [[Series/PowerRangersDinoThunder Black Dino Thunder]]), may [[SecretIdentityIdentity not remember who Tommy Oliver is anymore. That he's been a Ranger for so long that his entire identity is defined by a morpher, with no real conception of how he fits into the world as a person]].
** Not to mention he's suddenly very aware of how terrifying it must have been for [[TeamDad Zordon]] to see his protegees risking their lives on a routine basis.
** Shortly after Jason David Frank's death, [[WordOfGod Jackie Marchand herself]] [[https://twitter.com/jackieyo/status/1594412241662590976 confirmed]] that Fighting Spirit was a "not-so-veiled metaphor about battling your inner demons".
* Kira's death stare after being brainwashed by the Fossilador in "The Missing Bone". Fossilador has obviously never heard the expressions HELL HATH NO FURY LIKE A WOMAN SCORNED and BEWERE THE NICE ONES, So it appears he had to learn them the hard way.
* Trent's entire situation throughout the series. He's living under the same roof as a guy with a SuperpoweredEvilSide that could break out and hurt him at any time, gets corrupted by an unstable Dino Gem and has to live with the stress of keeping his father's condition a secret from his friends until it all comes out.