Lack of Tweek's speaking roles.

[Zhoaer]

I just counted, Tweek has not had a speaking role in 149 episodes STRAIGHT! That being "Child Abduction is Not Funny" and "Informative Murder Porn" This also includes the episodes "200" and "201"

Have Matt and Trey stopped loving Tweek? I know they said the love every character equally but wasn't a few years ago? Tweek needs a comeback. I hope he doesn't end up like Pip.

[Nico8300capo]

The reason Trey and Matt stopped using Tweek is because he isn't a really important character. He's kind of like Professor Mephesto, Jimbo and Ned, or Pip. They were fun at the beginning, but they started getting dull and boring, therefore getting less and less episodes. Dr. Mephesto's last important appearance was just a small cameo in 200 and 201, and Ned didn't have a speaking role since season 6. Pip getting squashed by Mecha Streisand was just a small cameo before killing him to shut up everyone who wanted him back.

[Big-Will]

The reason Trey and Matt stopped using Tweek is because he isn't a really important character.

In reality, it's because his voice was hell on Matt's vocal chords, and Matt's not getting any younger.

[Mamont]

Oh... I didn't even think about that. It explains a lot.

[zzyzx 2]

.... Pip getting squashed by Mecha Streisand was just a small cameo before killing him to shut up everyone who wanted him back.

Didn't work. Many still want him back, ala Kenny always returning after death. It's still possible (but it will never happen).

The reason Trey and Matt stopped using Tweek is because he isn't a really important character.

In reality, it's because his voice was hell on Matt's vocal chords, and Matt's not getting any younger.

*snap* I completely forgot about that. I'm sure the computers used to make the show could replicate Tweek's voice with Matt talking normally, but I doubt any effort will be put into that. At this point (Season 18), Tweek is just another member of the 4th grade class.

[agent-FSS]

In The Stick of Truth Tweek was voiced, but certainly very little. I still don't understand what needs to vocal cords so as to to speak in the same way? If to find a replacement impossible remaining outlet - misadventure ...

[Tweeks_Coffee]

I just counted, Tweek has not had a speaking role in 149 episodes STRAIGHT! That being "Child Abduction is Not Funny" and "Informative Murder Porn" This also includes the episodes "200" and "201"

Not true. He had a one line in Free Willzyx and he was the gnome on fire in Make Love not Warcraft.

Yeah, sadly most of the old side characters have been left for new ones. Most unfortunate is the addition of Butters as, let's face it, a major character.

ETA: Scratch that. I guess he didn't talk in FW

[BeRzEcKeR2]

I just counted, Tweek has not had a speaking role in 149 episodes STRAIGHT! That being "Child Abduction is Not Funny" and "Informative Murder Porn" This also includes the episodes "200" and "201"

Have Matt and Trey stopped loving Tweek? I know they said the love every character equally but wasn't a few years ago? Tweek needs a comeback. I hope he doesn't end up like Pip.

Between "Child Abduction is Not Funny" and "Informative Murder Porn", Tweek talked in the episode "Eat, Pray, Queef"...

So it weren't 149 episodes straight, but 94 episodes straight... (Unless I also forget about a speaking part.)

But I totally agree Tweek should be used more...

He's not even in the classroom anymore... The last time a former relevant character disappeared from the classroom, he was not seen again in the series until he was killed. (Pip)

At least Tweek still shows up in some other scenes...

I will keep hoping on a (semi) Tweek episode in the future.

I didn't like theme a couple of years ago, but when I rewatched season 6, I totally liked the guy Go Tweek

Edit: He also talked in "Make Love, Not Warcraft", so he didn't talk 57 episodes straight at max, that period...

Tweek has a lot more of (rare) speaking moments than we remember... But it can be more...

I hope Matt will try to voice him again for one full episode (at least)...

[JVM]

The OP is right in spirit but wrong in actuality. Tweek had at least one line later in season 6 ("The Return of the Fellowship of the Ring to the Two Towers") and a handful in 7-8. I can't pinpoint exactly.

Tweek's recent speaking roles in the last ten years, almost all of which have been limited to a single line, save the games:
Free Willzyx (s09e13-ish I think?)
Make Love, Not Warcraft (s10e08)
Eat, Pray, Queef (s13e04)
South Park: Let's Go Tower Defense Play!
Informative Murder Porn (s17e02)
Black Friday (s17e07)
South Park: The Stick of Truth

For an additional note, I think a lot of people might find it interesting to note he has zero lines in South Park Is Gay! despite his prominent appearance there with Craig and co. I'll add that his appearance in "201", while part of the background, was a prominent cameo, and based on his dad having a line, intentional.

As for the classroom? My archives are a little incomplete, but his last regular classroom appearance was in season 12's "Breast Cancer Show Ever" - he and Francis disappear by "Elementary School Musical" just a few weeks later. Since then, I've only ever spotted him in season 15's "Royal Pudding", although I don't have images on-hand post s17.

It surprises a lot of people to realize that Tweek, outside his run as the fourth main character in s6, has always been somewhat of a minor character -- take away that run and he's had less prominent appearances than Jimmy, Timmy, Craig, and probably Clyde. He's a fun character with a lot of potential, and I'm a big fan of him and his family myself, but he's barely even part of the kids' extended gang anymore. He's still a highly merchandisable fan favorite.

I assume like Big-Wil suggested, it's a voice thing and the fact Tweek comes off two-dimensionally. There's opportunities for development and depth, but I don't think Matt and Trey see them. But given his prominent role in the game, I think they're well-aware he's a fan favorite and just don't know how to use him.

The reason Trey and Matt stopped using Tweek is because he isn't a really important character. He's kind of like Professor Mephesto, Jimbo and Ned, or Pip. They were fun at the beginning, but they started getting dull and boring, therefore getting less and less episodes. Dr. Mephesto's last important appearance was just a small cameo in 200 and 201, and Ned didn't have a speaking role since season 6. Pip getting squashed by Mecha Streisand was just a small cameo before killing him to shut up everyone who wanted him back.

Ned last spoke a single line in season 5's "Here Comes the Neighborhood" but was voiced for the Tower Defense and RPG game like Tweek. Trey can't do the voice quite the same. Before 200/201, Mephesto last appeared in "Cartman Joins NAMBLA" and Trey suggested they should've written him out permanently by making him a pedophile. Before "201", Pip last spoke in season 4 and "Professor Chaos".

It's ridiculous how naturally this sh*t comes to me.

Related, but far from relevant:

nall: cvncv asks, what happened to Tweek? is he gonna be featured in any upcoming episodes

MattStone: yeah! We gotta do something with Tweek! Ask and you shall recieve!!!!

11/15/05 here on SPS -- think this was right before Willzyx.