Off the top of my head when it comes to the genres I read the most:
-The Girl with the Dragon Tattoo. The nordic thriller genre was highly prolific well before it, at least since the 1960s, but Larsson popularised it to a wider non-Nordic public by introducing cartoonish, exaggerated, violent, movie-like elements that contrasted with the tradition both of Nordic thrillers and of crime novels in general, and formed the basis for many successful writers that came afterwards.
-Battle Royale. Pulp, extreme and theatrical, it is a landmark of dystopian fiction that IMHO deserves to be in the same realm as 1984 and Lord of the Flies (not necessarily in prose quality, but part of it is because it’s not in English originally and the translation is bad) and is perhaps the single most important work of the whole “killing game” sub-genre.
Harry Potter is an obvious choice, The Giver as well (its exactly 30 years old actually so that’s crazy), A Song Of Ice and Fire, and this last one maybe will sound a bit stupid- but Invincible completely redefined the Comic Book Genre imo. It’s (almost realistically) violent, it goes against many consistently used comic book tropes, it tackles uncomfortable topics nobody really talks about (like >!When Mark is raped by Anissa!<), and unlike every comic book series ever, it has a definitive ending and let’s its characters have a concrete, definitive, un-retconnable character arc that ends completed, instead of constantly rebooting and de-aging the characters and keeping the main hero from his perfect soul mate (sigh. . . Spider-man). Seriously an amazing series.