Catharsis Factor: Finally killing Nemesis for good in the Final Battle after he's been chasing you this whole game is one of the biggest examples of this in the series.
Demonic Spiders: Hunter Betas. They aren't quite as hardy as their Alpha cousins, but they're twice as decapitation happy and they don't always wait until you've hit "caution" before they swat off your noggin. They also have an infuriating habit of appearing in groups nearly every time they're encountered and are damn near impossible to sneak up on, as you could often do with the Hunters in the first game.
Nemesis is one of the series' longest standing popular monsters. He is highly regarded as the best thing about the game and for contributing a Paranoia Fuel feel to the game that was unlike the series ever had before.
Nicholai is surprisingly popular with a great deal of the fanbase. Sure he's a huge jerkass, but he's also a deliciously Large Ham and extremely Russian. He also has the distinct honor of being like HUNK as the only surviving Umbrella operative.
Evil is Cool: Nemesis. The difficulty in fighting him didn't stop fans from loving him for the threat he poses.
Goddamned Bats: Crows of course, but the baby spiders are even worse, as their attacks cause next to no damage, but still interrupt Jill and Carlos's ability to attack, leaving them vulnerable to the far more dangerous webspinners.
Good Bad Bugs: The "corner bug" when fighting the eponymous Nemesis in the police station. If you lured Nemesis into the room where you find Marvin and backed into the corner next to the bookcase, then Nemesis would get stuck on the bookcase while trying to run at the player, keeping him just out of range to attack (unless the player is standing with the knife readied to attack and even then he'll only attack on his initial charge), allowing the player to attack him without getting hurt, even with their knife. He does eventually get unstuck but he can be lured out and back into the small office and this bug can be repeated until he's dead. This is the only viable way to beat Nemesis inside the police station without using a lot of ammo or healing items as shown here.
Hilarious in Hindsight: A bit of an obscure one. In the Versus Books Perfect Guide for Resident Evil 3, the author, as a joke, pointed out the various similarities between Nemesis and Sagat from Street Fighter. At the end he hoped that "Street Fighter vs. Resident Evil [happened] someday soon!" Fast forward to 2011 and Nemesis is one of the playable characters in Ultimate Marvel vs. Capcom 3.
Polished Port: Like the second game, the Dreamcast port of this one provided support for the VGA box and some additional bonus costumes, as well as using the VMU as a health monitor, all for a discounted price at launch.
Scrappy Mechanic: Your main source of ammunition in the game is gunpowder, together with the reloading tool. The bottles come in three varieties, A, B and C. This can be a huge pain in the ass to manage. Not only do you have to do more inventory shuffling than before, keeping track of the combination mixes, but the game randomizes the location of pick-ups. You can find yourself easily screwed over if the game decides to be stingy and not give you any gunpowder needed for magnum ammo.
Jill's short text narrations where she talks about how Umbrella took everything from her, including her home, are pretty saddening.
Dario Rossi, the crying fat guy at the start of the game who watched his daughter get eaten by zombies. You can go back after you are done in the police station to find him eaten alive by zombies.
Brad's Cruel and Unusual Death via Nemesis. As if getting bitten by zombies to the point of infection wasn't enough, one must remember that Brad's a pilot, not a soldier, meaning he's not as experienced as Jill, Chris, or Barry when it comes to combat. Just for his troubles, he gets to meet the business end of Nemesis's tentacle arm, and as implied by Jill's horrified reaction, it wasn't pretty. This scene reveals how Brad became a zombie.
Mikhail's Heroic Sacrifice to stop Nemesis especially if one recalls how Mikhail grieved for being the sole survivor of his squad moments earlier. Even Jill, who was initially doubtful of the Umbrella mercenaries, was visibly saddened.
The diary entry of the mercenary found in the Clock Tower with the girl he was trying to protect. At the end, he says he wanted to do the right thing. He did.
After the fight at the Clock Tower with Nemesis, Carlos, if he didn't destroy Nemesis's rocket launcher, will appear and prove that He Really Can Act by begging Jill to wake up.
The ending. Seeing Raccoon City being decimated with all those helpless people turned Zombies as Jill, Carlos and Barry Burton watch from their helicopter is absolutely heart-wrenching. Not to worry, it gets much worse. We are then treated to a still of a large mushroom cloud following the nuclear explosion as we are fed a news story informing us that other than Jill, Carlos, Leon, Claire, Sherry, Alyssa, Kevin, Cindy, Mark, David, Jim, George, Yoko, Ada Wong, Barry Burton, HUNK, and Nicholai there were no survivors. Yep, all 100,000 people vanished. All while this heart crushing track is played in the background. This is followed with even further heartbreak with this sad, but beautiful track.
The fight with Nemesis at the Clock Tower is one of the toughest boss battles in the game. You have a very limited space in which to fight him in, and he will often knock you down, then pick you up and do a One-Hit Kill move. Plus, you can't see your health indicator anymore.
While there are tricks and tips available to beat him, Nemesis in general can be really nasty if one is going to slay him for the weapons. If only because he'll pick fights with you in hallways where you're at a disadvantage in fighting him.
Taking out the big guy in first encounter outside the Police Station, should only be attempted, if you are a glutton for punishment. You are practically naked at this early point in the game, with little ammo and herbs. Be prepared to die and die, and die.
That One Puzzle: That godawful water treatment puzzle. Even after you figure out the "gimmick" to solving it (all three meters combined = pattern on bottom), you'll still need to be very meticulous in visualizing exactly how each meter should line up, and it's randomized.