- Angst? What Angst?: In BFE, Sam barely seems to register the early-game death of his squadmates as well as the frequent deaths of all the various allies he's supposed to meet up with. He doesn't even give the perfunctory "shit that sucks" that most other FPS protagonists give out after such events.
- Awesome Music - "Dunes Medium". Yes.
- And the third battle theme from Second Encounter.
- Can't mention The Second Encounter without the Grand Cathedral theme!
- Ugh Zan III's boss theme.
- The Great Pyramid.
- What? No love for the Mental Institution theme in Serious Sam II?
- The main menu theme of The Next Encounter. While it's not the best soundtrack from the Serious Sam series, it sure makes you pumped for action.
- Boss Fight Strings from Serious Sam 3: BFE
- Best Level Ever: A relatively small war sequence is found in the First Encounter level "Dunes". Fun as hell. Crowning Music of Awesome also helps a lot.
- Non Sequitur Scene - The House Of Sam trailers for Second Encounter HD, starring a unstable televangelist spreading the good word about The Second Coming Of Sam. Krundle Blind! KRUNDLE BLIND! KRUNDLE BLIND!!
- Demonic Spiders:
- Carpet bomber planes at the final boss of II are difficult to hit and even more difficult to avoid. Chaingunner zombies are like arachnoids in the first game, but they're much quicker when it comes to firing at you and they do more damage.
- Technopolip-possessed Apache Helicopters are also troublesome since they're immune to bullets and some of them are encountered before getting the devastator or a cannon which is annoying since they tend to move out of the way of your rockets all the time. That, combined with their powerful hitscan machine gun, makes them incredibly frustrating enemies on higher difficulties.
- Adult Arachnoids in BFE are a huge problem at higher difficulties, since they do more damage than Arachnoids in the previous games and tend to move out of the way of your rockets rather than standing still like their classic counterparts.
- Fiendian Reptiloid Demons in The Second Encounter are very potent enemies. They have a very high amount of health, so much that it takes four sniper rounds to down them on Normal (practically every other enemy goes down in one or two), and launch extremely fast and damaging homing fireballs that can't be destroyed by anything other than the lasergun, cannon, or rocket launcher. They also have a punch that kills you in three hits if you have maxed out health and armor, but chances are you'll never even see it because eighty percent of the time they are placed in far off places or on top of buildings to spam their fireballs at you. If that wasn't enough, they never flinch, unlike ninety percent of the enemies, and they can use fireballs to block your bullets, which is not obvious upon first fighting them.
- Difficulty Spike: The final boss at the end of the PC version of Serious Sam II's final level Mental Institution. First off, if the vehicle you need to destroy the boss with gets destroyed, you die instantly. Not only that, it can summon planes that either collide with you, carpet bomb you, or just shoot at you as well as launching out cannon balls and big fireballs. The carpet-bombing planes will rape you if you don't take them out before they let their bombs loose on you.
- Excuse Plot - Can be read here. Tries to justify the action going on.
- Funny Moments - "To be or not to be... that is a serious question."
- Also, this line from the BFE trailer, which may double an Awesome Moment:
Sam: It's not over until I teabag every last one of you alien motherfuckers.
- The secret watcher in Second Encounter, especially when you shoot at it.
- Game Breaker: Serious Bomb in Serious Sam 2, which instantly kills everything else within a quarter mile. Especially in multiplayer with unlimited ammo. They're pretty spam-proof in The Second Encounter, though, even being immune to the "giveall" cheat.
- The Next Encounter has the sniper rifle... Oh god, the sniper rifle. Argueably, its' might even surpasses the one SBC Cannon has, making it a whole ton less reliable.
- Gameplay Derailment: Using your co-op mate as a platform to get the secret above you both. It stopped working since BFE came out, though.
- Goddamned Bats
- In Serious Sam I, marsh-hoppers, kamikazes and kleer, latter of which are the most common enemies... ever. Also, the Arachnoids, mostly due to being the only enemies in the game with hitscan projectiles. Sirian werebulls are like kleers but worse, given that they have more health and tend to knock you around in massive hordes while dealing high damage to your health, though it's also generally easier to avoid them. Aludran Reptiloids stayed back and fired fast, homing green energy balls at you, usually from a high vantage point. They tended to do this when you were in the middle of an encounter with melee enemies.
- In Serious Sam 2, flying enemies, most notably witches, floaters, and harpies. Fatso Fighter and Seagull Bomber planes to some extent too due to being hard to hit but rather easy to avoid.
- In Serious Sam 3, the kleers, werebulls, arachnoids, and kamikazes make a return, and several new annoying enemies are added. Some of the worst are the cave demons, cat-sized predators who leap around and lunge at Sam in dark areas. On Serious and Mental difficulties, the cloned soldiers (weak, inferior, cannon fodder versions of human troops) become this as well. They only take a few shots to kill, but there's tons of them, they have hitscan weaponry, and can slowly cut down your health while the goddamned kleers rush you.
- There's also the Witch-Brides, Superpowered Mooks with telekinesis and invulnerable, damage absorbing barriers. Their telekinetic attacks do little damage, but they constantly teleport around and are invulnerable unless they're attacking, meaning they take far longer to die than they have a right to. What makes them so annoying is their 'choke' attack; they lift Sam up into the air, stun him, and inflict minor damage; this basically mean every single enemy in the area will instantly start ganging up on you until the attack is over while you are completely unable to defend yourself. On any difficulty above normal, getting hit by this attack is basically instant death.
- Hell Is That Noise: The kamikaze bombers scream:
- Ugh-Zan III, though less intense examples abound. Like the fight before that.
- The entire last level of The Second Encounter.
- It Gets Better
- The first two levels of "The First Encounter" play out like a standard early FPS. Then you get to the end of third level, and suddenly hundreds of enemies start spawning all at once and running towards you. That's when the real game kicks in.
- BFE starts you out very slowly. You have to use a hammer at first, don't even get a pistol until some way into the first level, and only get the serious (heh) firepower and battles after quite a while.
- Mondegreen: "WAAAAAAAAR!!!" often gets interpreted as "MOOOOOOOOOORE!", "GOOOOOOOOORE!", and "WHOOOOOOOOOOOORE!", among other things.
- Most Annoying Sound:
- The villagers in Serious Sam II say "HIIII" "HELLO" "HEEELP" "YIPEE" a lot.
- Gets real annoying with the Kamikaze Bomber: AAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHHHHHH...
Serious Sam: AAAAAAAAAAAAAAHHHH put a sock in it! [More screaming is heard] Uh-oh!
- You will learn to loathe the sound of galloping Kleer skeletons. NETRISCA even lampshades it.
- Non-Indicative Name: Any of the games.
- Paranoia Fuel: Whenever you are in an area where there are inactive enemies either hiding or waiting to spawn, the game plays a randomised loop of growling, snarling and screeching. It stops the moment you've wiped the area clean of foes, but until then you'll find yourself treating powerups with the utmost suspicion and jumping at every single sound (especially if you're low on health).
- That One Achievement: In 3, "Queen Hatshepsut" which requires completing the final level in single player on serious difficulty without dying or reloading. The level itself is quite difficult and par time of this level is 80 minutes.
- That One Boss: The Zerg Rush of marsh hoppers in The First Encounter is this to some.
- As is the final boss of II.
- That One Level / Best Level Ever - "The Grand Cathedral" from Second Encounter, while very impressive, is also clogged with enemies. The "Great Pyramid" from First Encounter, slightly less so. This is actually the best part for some players, since it gives a nice "Holy fuck!" feeling the first few times. The hardest difficulty also requires the players to perform some sort of slot puzzle in order to enter the pyramid to kill Ugh-Zan.
- The Guardian of Time in BFE is basically both of those levels taken Up to Eleven.