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X-4 Sigma L | Fansproject Function X

X-4 Sigma L | Fansproject Function X


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Product Specs

Manufacturer Fansproject
Size 6.0 inches
Scale Voyager Class
Series Function X
  • MISB (Mint in Sealed Box)
  • Case Fresh From a Factory Sealed Case
Alt Mode Bat

Out of Stock


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Product Description


X-4 Sigma L | Fansproject Function X

ToyGeek code: FPFX4-FUNC-SIGMA-L

Fansproject figures take your collection to the next level with X-4 Sigma L, a Voyager Class scaled 3rd party figure transforms from Bat to robot and back. 


X-4 Sigma L by Fansproject stands approximately 6.0-inches tall in robot mode and is part of Fansproject's Function-X Series of figures.  Each figure features a transforming robot head that also functions as a driver when the main robot is in vehicle or beast mode.   Each figure is approximately Voyager scale and scales to other figures in the Function-X toyline. 


Fansproject's figures feature modern engineering techniques and toy design and are made of high quality ABS plastic. 


Start your Fansproject collection today with Function-X X-4 Sigma L.  Add this highly sought after piece to your collection today at Toygeek - your source for 3rd Party collectible transforming figures.

Product Features

  • Toy Series: Function X
  • Scale: Voyager Class
  • Alt Mode:Bat
  • Third party figure
  • Mini figure transforms into Sigma L head
  • Made of plastic
  • Product is brand new and in mint condition
  • Toy Size: 6 inches

Packaging Contents

  • 1 x X-4 Sigma L Figure
  • 2 x Blaster Weapons
  • 1 x Mini Figure

WARNING: All items sold by Toygeek are intended for adult collectors. Items may have small parts or other elements not suitable for children under 16 years old.

Customer Reviews


Customer Reviews

5 out of 5 stars overall


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Geneva, IL

October 11, 2022

This take on Mindwipe is awesome. The joints are nice, it can stand on its own very well. I love the detail of the “coffin” on the back in bat mode, and the speaker details. The only problem I have is with the head master. It doesn’t really like to fold up all the way. However if you don’t like using the headmaster as the head, the beast mode can be used.

Stoughton, WI

June 12, 2021

Looks outstanding in robot mode. Bat mode has a neat gimmick on the back where there's a cross on a coffin that opens up, revealing the headmaster inside!

Elyria, OH

October 05, 2020

This guy looks great! The colors are awesome and I really dig the dynamic with the little robot pilot transforming into the head!

North charleston, SC

May 27, 2019

Great figure for its price! Good for those who want something beautiful with amazing details, but don't wanna spend too much. Figure is built slightly loose (easy for head/minirobot to undo itself, no stiffness in arms or wings, and the waist is basically sliding). As a decepticon fan, his detail, color scheme, and alltogether look is amazing. In the long run, I recommend buying it if the pictures appeal to you.

Hafnarfjörður, gullbringusýsla

December 25, 2018

This is my first Transformer that I order online and I am very impressed by this figure. Everything is in great detail, the paint scheme is awesome, both robot mode and bat mode look incredible. Did I mention just how cool he looks in robot mode? Well he really does, put him in a combat stance sporting dual shotguns and the ability to customize the wing shape to close combat function and you´ve got yourself a mean machine brawler Decepticon. Transformation is rather easy and very intuitive, you can even put his head figure inside a cockpit on the bat´s back! Perfect third party Transformer, 5/5!

Port hueneme, CA

October 22, 2016

I bought this for fifty dollars but would've paid full price if I'd seen one up close. The plastic is top notch the joints feel great and the transformation was a breeze. Only complaint is the visor is stuck in the up position and I'm afraid to push on it too hard but no big deal.

Decatur, IL

October 07, 2016

It is getting to the point where I prefer third party products. The amount of detail on this figure is absolutely amazing! The wings fold up and even pose in a spectacular display that I never would of imagined! In bat mode his wings fold up entirely and makes it look like an actual bat crawling around!

The robot mode is sophisticated and has a very nice pose-ability once you figure out how to adjust the wings correctly. A lot of people pose this figure with the wings behind, but I like to display with the wings out and curved a bit. It just looks amazing. This figure has re-sparked my enjoyment for transformers and my desire for collecting them! My favorite parts are the wings and the bat head, plus the ingenuity for the legs.The sheer amount of work that goes into figures like this is in a word..awesome.

Altadena, CA

July 24, 2016

He is one of the few Headmaster figures where you can actually transform him without taking off the head: Turn the headmaster head 180 degrees & fold the body into the back, then close the cover over it to complete transformation.

He's worth getting because of solid plastic, tight joints and a simple transformation! Not to mention, he looks great in both modes! Not sure why a vampire has 2 shot guns instead of swords or knives, but they both look great, too.

Glad I picked him up!

Port hope, Ontario

June 25, 2016

FansProject did a great job with this guy. Its wingspan is huge, and has many joints to adjust to one's liking. The "headmaster" compartment is a freaking coffin in the back. The robot is suitably cool and creepy, whether or not the included shotguns are held.

However, I do wish the wings could fold up better, as they take up a lot of room. I also wish the bat head tabbed in somehow in both modes. Still, a worthy addition to one's collection.

Wichita, KS

June 12, 2016

This guy is nearly a perfect display piece in bot mode. I got the soul eater scythe for him which still shows really well dispite the slight color difference.
My complaint is with the alt mode and its lack of inginuity. The bat claws should be on the wings not the shoulders and the double tail is obnoxious. Obviously this was not a deal breaker but it does limit the display to pretty much bot mode only.

Cibolo, TX

January 13, 2016

i love sigma he is an awesome new look of g1 mindwipe, but the with mine the visor snapped on the head-unit right as i took him out of the box, i was a little upset bout it but i still love him and he is a must have.

Hornell, NY

December 08, 2015

I just got this figure in and I love it! Transformation isn't overly complicated, posability is really solid, It just feels really solid. I would definitely recommend this figure.


October 27, 2015

I just got this figure and words aren't enough. All I can say is Fansproject has out done themselves on their version of MindWipe. The colors and features are second to none and the transformation is somewhat simple, but that doesn't bother me or degrade the figure in anyway. Yes the wings are fixed to his shoulders and can get in the way of some poses, but I think this adds character to this already awesome figure! Highly Recommended and looks great with Dr. Wu Soul Eater Scythe!

Tujunga, CA

October 06, 2015

I got to like this figure more then I thought I would.the details are excellent. The only issue I had was the head that's a robot too one of the arms was lose out of package. It seems to me maybe a manufacturing issue with mine.

Magnolia, DE

December 13, 2014

I was sooo happy with this guy his size and features. He is like the count dracula of transformers. The way they made him was awesome

Royal oak, MI

November 10, 2014

If you're buying Sigma L for his looks and durability, you will likely have no complaints. His robot mode is an amazing vampiric badass, and the plastic feels solid enough you could chuck him down the stairs without worry.

But what I've liked most about the other FP headmasters has been their amazingly inventive transformations, and this is where Sigma L was a major disappointment to me. I was so hoping he was a little more complex than how he looked from the photos, but no. Instead of the brilliant shapeshifting of Code or Smart Robin, Sigma basically folds up into a rectangle with awkwardly-proportioned bat parts stuck on. The laziness is exemplified by the fact that his robot arms aren't even hidden in bat mode, and the feet could have easily rotated inward to become a tail, but no, instead they just hang off his butt as kibble. The coffin-cockpit is easily the most creative part of the toy, but even that's marred by the toy's overall stiff tabs and joints, making transformation and posing just feel unpleasant.

For the others in this line, great attention was paid to both modes. With Sigma, he is basically a truly gorgeous action figure that happens to have a transformation. In contrast to some figures I own where I keep noticing little touches where the designer went above and beyond, Sigma feels like a first draft. As if every step of making him was solved with the first, most obvious idea that popped into the designer's head. Maybe my expectations were too high, but maybe the creativity of the previous three raised them to that point.

Burnsville, MN

October 19, 2014

FP continues to make awesome figures with Sigma-L. The Function-X line consists of great figure after great figure, and Sigma-L is no exception. While he's not quite up the level of awesome engineering that FP demonstrated in Smartrobin, he's still a fanastic figure. Coloring and posability are top notch, though his weapons don't integrate as well into his alt mode as the other Function-X figures. Still, that's a minore quibble, and Sigma-L is definitely worth your time and money.

La, CA

October 17, 2014

Appearance: 5.0
Articulation: 4.5
Transform Complexity: 5.0
Material/Chrome: 5.0
Mold Precision: 4.5

Overall Rank as a collection: 5.0

Fantastic action figure.
Better than WB000 WB001 WB002
Better than CA03 CA04 CA05
FPJ is making progress.

Fort lauderdale, FL

October 10, 2014

Have to give it to fansproject they know how to make toys.... It have some weight to it and is not light like Smart Robin, Weird Wolf or Code. The transformation is fun and just looks great. I can't wait to see what they do next.


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