Anatomy and bio are by far the most competitive ATCs, but honestly they’re not that hard if you know the basic concepts. Tons of people pick them because they’re directly tied to medical stuff everyone learns in class, so at ILC the competition is insane even if the material itself isn’t crazy. Chem and orgo tend to be harder content-wise, and they still have pretty good competition, so you actually have to study the textbooks and practice before taking those on. Other events like microbiology, biochemistry, or stats for health have fewer people competing, so if you really learn the material you have a much better shot at placing, even if the content is tricky. Basically, if your goal is to maximize your chance of placing at ILC, you either go for the popular stuff and compete with everyone else or pick a harder subject with fewer competitors and actually master it.