The dissonant sounding "God Save the Queen" at the end of the Royal Wedding Tat review. At least before it's apparent that the music is breaking.
Any occurrence of Noseybonk, a little-known source of Nightmare Fuel from the old British 80s Game ShowJigsaw. Yeah, an already unnerving entity gets made even more terrifying. Even better, Ashen's Noseybonk mask is scarier than the original!
In his review of Girl's Toys, he brought up a doll dressed up in wedding garb. This wouldn't be so bad if not for the positioning of the doll's eyes inducing this trope with a very big bang.
The Creme Egg knockoffs in the Easter Tat Special were disgusting and rancid, but not initially horrifying. And then Ashen finds a maggot in the middle of a candy piece. Though admittedly a fake one, planted as part of a behind the scenes prank.
What he actually did is known as Circuit-Bending. Basically he cut off the outer coating (skinned it alive) then fiddled with the internal circuits. The result made it sound like E.T was being brutally murdered while his screams were muffled. This combined with Ashen's speech about how he is going to make it better causes it to be nightmare fuel. Now, imagine E.T was sentient...
It gets worse. After the traditional ASHENS.COM at the end of the video we see E.T.'s rubber face pinned to a corkboard.
The Stock Clearance Special, when Fridge Horror hit Ashens on how the "Cutants" are, in Polly Pocket's world, alive and sentient. He gets upset by the idea, and he decides to make a horror short to illustrate just how scary things would be if Polly Pocket and her group of mad scientists decide to move on to humans and were to come after your girlfriend...warning Contains unhealthy high doses of Uncanny Valley And Body Horror
You wouldn't expect a semi-Christmas related advent calender to have anything terrifying in it, right? You'd be wrong. Hell, the grass masks in general. From assimilating both deer to hanging Santa from the tree by his sleigh.
The grass masks return in the 2014 Block-Tech advent calendar series. For the first 21 days, they do nothing but pop up occasionally and be very unsettling, which is exacerbated by the fact that Stu never once so much as alludes to them during the main videos. On the 22rd day, Stu finds a handful of grass stuffed into the sofa. On the 23rd day, we have... this... And on the 24th day... well, see for yourself.
One of his earliest videos in the PO Pstation Saga is a review of one of the games that frequently comes pre-installed on the rotten little pieces of trash, Submarine Invasion. The review itself is significantly shorter than the run time of the video, but Stuart managed to fill the leftover time... by using somewhat grainy grayscale video footage of someone in a white lab coat and what appears to be a welder's face mask fiddling with a machine that rattles off lists of numbers. That's all the extra footage consists of, and it's deeply unsettling.
His Big "Shut Up!" to the iPhone 5G was rather convincing, to the point that it does paint an ugly picture about what he could be like when set off.
His take on the Drawn My Life meme. Wait, how could he make a fad like this disturbing? Well...
His Viewmaster Stereoscope review has a really dark turn at the end where he plays the "Little Red Riding Hood" slide on the JR. Projector. Before that, Ashens commentary on the previous films were hilarious and descriptive, until that shows up. Ashens narration in this is monotone and bluntnote made even worse that he's actually reading the descriptions seen on the slide, and combined with the unsettling claymation models and creepy music made it rather disturbing.
In 2011, his announcement that he would be making videos full time, seen here. Or if you'd prefer the "director's cut", in which he adds a painfully brickwalled "Morningtown Ride" by The Seekers in the soundtrack.