These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
The air taser, wihout a doubt. Infinite range, infinite ammo, considered a stealth weapon, can kill a helluva lot of baddies in relatively short time plus its fun to hear them scream and see them catch on fire.
In The Omega Strain, the E.P.D.D., an advanced version of the air taser, is arguably the best weapon in the game, as it has ridiculous range, and can sometimes punch through flak jackets (usually in two hits), meaning that you can kill almost anyone you come across.
Good Bad Bugs: In The Omega Strain, enemies will sometimes appear with weapons stuck in their necks, making it impossible to shoot the player, who can run around without fear of being hit. However, it can happen to the player as well.
Harsher in Hindsight: In 2, about halfway into the game, Lian Xing arranges a meeting with a former partner, Uri Gregorov, at a neutral meeting point: a techno dance club. But their meet-up is ruined by an attack on the club to try and assassinate Lian. And the date that this happens on in the mission dossier? 09/11.
It's the Same, Now It Sucks: A common complaint is that the original trilogy's barely changed over time, in both graphics and gameplay.
"You're runnin/almost outa time! PICK UP THE PACE!"
Imani Gray is one of the most irritating characters in the Syphon Filter series, because she's constantly yelling/whining at you to do something, or to pick up the pace. Which makes her death all the more satisfying.
That One Level: Syphon Filter, along with Metal Gear Solid, was one of the first games in the modern era (starting with the PS1 onward) to use stealth and cover tactics to accomplish a mission. Notable examples that could still frustrate gamers today:
In Washington, D.C., there was the tennis court level where you had to make precise silenced-night vision sniper shots.
The museum level relied on evading or shooting multiple mooks.
The snow base level. You had to plant C4 on each of the base's fuel tanks while remaining unseen by the mooks. And the subsequent base tower level, which required you to have enough ammo to fend off a helicopter whose pilot shot automatic rounds at you.
The catacombs levels were sprawling. Fun to play, but extremely open world for its time.
The PHARCOM warehouses. Infinite spawning mooks and very confusing layout. Also, you have to use the infrared-style device to get what you needed to advance, which were not at all easy to find, and you were not at all told that you needed to use them.
True, but if you used the "god mode"/"unlimited ammo" cheats, you turn the warehouse level into a shooting gallery.
The missile silo level required you to navigate a series of catwalks and metal beams to disarm the missile and escape before it launched.
The bonus missions in The Omega Strain have you playing characters from the earlier games (Gabriel "Gabe" Logan, Teresa Lipan, Lawrence Mujari, etc.). Sounds cool, right? The problem is that these bonus missions can be quite long, have multiple objectives, are all stealth based, and if you get spotted, it's an instant game over. And because there are no checkpoints, if you fail, you have to start all over again from the beginning.note Technically, you can still continue the game if you're spotted in Gabe's mission, but it's next to impossible to beat in the time limit you're given. This is especially problematic in Mujari's mission, where you have to sneak through a bombed-out village that has plenty of places for enemy soldiers to hide, and you can't kill any of them. The general consensus among Syphon Filter fans is that this is arguably the most frustrating mission in the entire series.
The Scrappy: Imani thinks she is Jack Bauer but ends up being a lot bitchier, constantly harassing and putting down the player, only to end up killed early in the game.