- Audience-Alienating Premise: Many people reject this series, accusing it of the extensive Pandering to the Base.
- Best Known for the Fanservice: For most people, most they can say about the story is that its main character is an extremely innocent little boy, looking like a girl. It's even regularly parodied in-universe. However some LN readers and those who came for the mechas, are pleased with the generous amount of screen time and action the Silhouette knights get.
- Cargo Ship: Eru really likes robots, to the point of ignoring the girls who are chasing him. Conclusions may be drawn.
- Cliché Storm: Not the story itself, but many of its characters and fanservice can fall into this.
- Escapist Character: Ernie full stop. Good-looking to the point of looking feminine? Check. Ridiculously talented in every subject imaginable? Check. Getting to build his own Ace Custom mechs that outstrip literally everything else in the world by a huge margin? Check. Being the virtually infallible leader of an entire squadron of mecha of his own design? Check. Prioritizes mecha over women? Check.
- Foe Yay: Upon seeing each other's flying machines, Ernesti and Horacio really want to get into each other's...technology.
- Heartwarming Moments: Ernesti, Kid and Addy have been childhood friends for a very long time which reflects on their teamwork which led to many amazing things happening. It isn't farfetch to declare that Kid sees Ernesti as his bro while Addy sees Ernesti as her future husband.
- Ernesti in his Ikaruga saving Kid from the falling ship.
- Moe: Central cast is actually based on this. A sweet, feminine boy? Check. Half-Identical Twins, interacting cutely with each other? Check. The Cool Big Sis who adores them? Check.
- Moment of Awesome:
- Ernesti using a damaged Guair to take down the Behemoth Demon Beast.
- The introduction of the Tzendorg, a centaur-shaped Silhouette Knight that brings a carriage of several advanced knights behind it.
- Ikaruga's first battle.
- Vyver vs Kid's Tzendrinble
- One True Pairing: The series hints to lots of them.
- Eru and Adel (he's apparently "doomed" to be her eternal pillow)
- Kid and Eleonora (seen miles away when they met)
- Edgar and Helvi (she likes him but he seems oblivious to her feelings so far)
- Dietrich and Nora (hinted on in the final episode of the anime)
- Rooting for the Empire: Zaloudek may be an Obviously Evil Empire, but there were many fans who actually wanted them to defeat the protagonists due to their seeming invincibility.
- "Seinfeld" Is Unfunny: While many light novel readers find the "death by truck crash" prologue an interesting start for most isekai novels, but given how notoriously common the idea has become, some find this example to be extremely overused and annoying.
- Spiritual Adaptation: Knights and Magic with a theme of tech race and power sources from within the core is the closest thing to have an anime adaptation of Armored Core
- Tainted by the Preview: Many people decided to pass on the anime adaptation when the announcement said this is yet another work about an otaku revived in a fantasy world.
- Viewer Gender Confusion: Eru is often mistaken for a girl both in- and out of the universe thanks to his extremely feminine appearance and a costume reminiscent of a dress. To make things more confusing, his seiyu was revealed to be Rie Takahashi, known for the role of shy girls (although she already had a similar role once).
YMMV / Knight's & Magic