Perhaps the most infamous and ruthless copy protection came in the form of the quirky SNES RPG Earthbound. Though you can play through the entire game, the pirated copies have a few important wrinkles. Namely, there are many, many more enemies, making the battles much more frequent and the game much more of a slog. But let's say you just call this "Hard Mode," and power through to the final boss. That's where the shit gets fucked.
Right when you're facing down the final minutes, the game freezes, without fail. The crotchgoblins who whittled away hours of their lives by trudging through an illegitimate, extra-difficult Earthbound no doubt quivered while their Cheeto fingers reached for the reset button -- only to find all of their progress erased. In that moment, Nintendo became the awful save-overwriting cousin that pirates deserve.
You can block pirates, you can make their game experience worse or you can leave a flaming bag of Olive Garden on their doorstep, but nothing beats good ol' fashioned public humiliation. It takes a lot of care to devise a plan to make pirates reveal themselves to the wider public, but when it happens, the schadenfreude ist durch das Dach. One of the most successful plots involved Batman: Arkham Asylum back in 2009. In the game, one of the early upgrades you get allows you to glide with your cape to previously unreachable places. In the copied copy, that cape doesn't work right and you can't continue the game's story. It wasn't long before some illiterate crumb of dickcheese posted the problem to the official forums, and was immediately outed as a thief by the developers.
Forum-shaming is pretty key here, as you'll see.
The developer of insanity farm Garry's Mod put an ingenious spin on this trope. Those who pirated the game would get a nonsense error that said "Unable to shade polygon normals," followed by an error code. The catch is, the error code was specifically tied to that person's online Steam account -- as a result, any pirate who posted that problem was gingerly placing their head on an anvil in perfect view of the banhammer.
This kind of self-induced flagellation has happened as recently as FarCry 4.
An FOV slider controls the field-of-view in an FPS; so basically, how much you can see on your left and right. It's an important feature for a lot of PC gamers, and apparently a lot of pirates. See, when FarCry 4 was leaked online, it didn't have that FOV slider -- it was going to be added in with a day one patch -- but the bootleggers didn't know that. When the patch details were revealed after the fact, the dweebs who'd been moaning about the absence of an FOV option were immediately outed as the crustiest of dingleberries.
This concludes today's justice porn marathon.