The body horror gore effects in The Substance (2024) were amazing. The rest of the movie was reasonably good, but I disagree with a few directorial decisions. It treats the viewer as if they are really forgetful or not paying attention (which is a direction that a lot of streaming is going iirc).
All the forced perspective in LOTR.
Bumping the Lamp. In Who Framed Roger Rabbit, Roger and Eddy are wrestling in a room and Roger (a toon) bumps into a ceiling lamp which starts to swing. Sounds simple and then you realise that Roger is drawn in and as Eddy is pantomiming a wrestling match the effects team managed to swing a ceiling light from off frame and made it look like a simple brush of a cartoons ear.
It's getting long in the tooth (pun intended), but the T-Rex scene in Jurassic Park where it attacks the cars still holds up.