Cthulhu Costume - Latex Body Suit




Introduction: Cthulhu Costume - Latex Body Suit

About: I've been making movies as a hobby for nearly 8 years now, and I've always enjoyed the fantastical and imaginative. I occasionally take on the challenge of trying to construct some recreations.
That time of year again. I must follow tradition and make a costume. But what costume could I make this year that would be more complex, more unique, and more impressive? In brainstorming, I was looking at classic designs, like the Alien, and I was reminded of influence that Giger cited, the literature of H.P. Lovecraft. Once the name "Lovecraft" came up, my mind went immediately to Cthulhu, of course.

I've made many costumes as replications of cinematic characters. But this was something different. Cthulhu is a strong part of the popular culture of recent generations, but is seldom seen in three dimensions. There have been a number of visual interpretations of the Great Old One, from video games to South Park. The public does have an image in their mind when they hear "Cthulhu". This character allowed for a costume that could be unique in several ways: it's a costume that no one else would have, or imagine me having, and people may not be able to tell I made myself, because of the complexity of the design and construction method. It would also allow me to be creative and make my own design. All of these unique prospects appealed to me. And I love the challenge of creating extravagant items on a low budget. Producing a full-body latex suit often costs into the thousands. My aim was for under $300.

Prior to my own costume, I had only seen one half-decently made serious costume of Cthulhu. Indeed, there have been many furry costumes and adorable plushies, as Cthulhu has been turned "cutsey". But it's time to get him back to his more monstrous form.

Here is a video you can watch that shows the overall process. It's easier to see some of the steps in motion, but the Instructable has much more information and is more detailed.

Step 1: Background and Research

I find it more engaging to make costumes of what I understand, so I sought knowledge of Cthulhu and Lovecraft; the history, the mythos, and his storytelling. Lovecraft often wrote about forces beyond our Earth, beyond our galaxy, even beyond our physical realm. As such, the entities within his stories are often impossible to describe, and do not look like any life form we know from our own planet. Cthulhu, at most, was described as vaguely anthropoid, with wings and scales, and writhing tentacles on his face. Creating a complete design out of such vague descriptions is a bit of a fool's errand. Lovecraft's work doesn't really lend itself to full visual depiction; it truly works best as a horror of the imagination. It's the impossibility of the entities and the vast cosmic horror of the mythos that causes terror within the reader.

So I had to admit right from the start that whatever design I came up with would probably not please any Lovecraft enthusiasts. And I don't mean to. This is just a costume for fun. An advantage of having such a vague description to work off of means I can do something uniquely my own. At the same time, though, I did want the average person to be able to immediately identify the design as "Cthulhu". So I stuck with the regular humanoid body and octopus-like head. Which was fine by me; designing is not my best strength, so it was good to have a base to work off of.

Once I decided that Cthulhu would be a good costume to make, I had to do some planning. How would I make this costume? I wanted it to be lightweight, easy to get in and out of, and highly detailed. Sculpting the body in clay, and making plaster molds for casting a latex suit would be a great challenge, but seemed like the best way to go. My first instinct was to make a body form with foam boards, covered with plaster strips for a body base to sculpt on top of. And then make plaster molds on top of that. But how to mold the body parts? Considering size and weight, I knew I would have to mold separate pieces (like the torso, arms, legs, and head) individually. But plaster can be very heavy, and expensive if you use a lot of it. Could I somehow make molds with a resin and fiberglass instead? I explored many potential methods. This researching, in addition to learning more about Cthulhu and Lovecraft, delayed my production of the costume. I started planning as early as late August, but didn't begin any actual construction until October.

Step 2: Building the Body Forms

I began to make the torso shape following the initial idea; making a form out of foam boards, and then building up plaster strips. But it was very difficult to get the shape smooth and detailed like a torso. It then suddenly donned upon me; there was an easier way. I could just mold my own torso with the plaster strips. This would be good for all of the body parts; I wouldn't have to build structures out of foam boards, and the body pieces would be hollow on the inside, making it easy to empty out the after they have been molded, just pulling the plaster-strips form and clay out of the plaster molds.

So I slathered Vaseline all over my torso, put plaster strips on the front half of my torso. I couldn't really reach the back half of my torso, so I put the front half onto a duct-tape mannequin I had made a while back. I then covered the back with plaster strips, making the whole torso piece on the mannequin. I then cut the sides to remove the torso mold, and then sealed the cuts to make it one whole piece. Reinforced with more plaster strips, and also joint compound, and I had a solid, nicely shaped torso pieces to sculpt off of.

I then repeated this process for my arms, legs, and also my feet. I would have stilts on my feet, so I molded my feet while wearing the stilts, to preserve that shape.

Step 3: Sculpting the Torso

I figured the torso would be the best piece to start with. It was the largest piece, and I knew if I could sculpt and mold that, the rest would be perfectly possible.

I used air-dry clay, so I could have a large amount of it for a conservative cost. I bought some WED clay from a local supplier, but also used pottery clay for later pieces.

Among other things, Cthulhu is often portrayed as having something of a gut. Indeed, the original text describes him (or at least a statue of him) as "somewhat corpulent". I started there, making a good prominent belly. Then moved onto the upper part of the chest, where I randomly decided to add gill-like structures. This was how I would sculpt most of this design; nothing specifically set in mind. I did look at other artists' drawings of Cthulhu for inspiration, but did want to go more my own way, so I just made it up as I went along. Then added some ridges onto the neck and shoulders. On the back, I went ahead and marked out a line down the middle; a split where I would eventually put a zipper.

Nothing very specific with my methods, just slapping on clay until it looked good enough. Especially with my relatively short schedule to stay on, I had to work fast. Luckily Cthulhu would have a body that isn't perfectly symmetrical, and could have abnormal growths here and there, and so it almost looks good that it's a bit untidy. That's my excuse at least. Heh.

I added some texture onto the sculpt; some scratched, wrinkly lines, and small indentations like pores, mainly using a rigid dry piece of cloth. And then a final spray of Krylon Crystal Clear to seal the sculpt, ready for molding.

Step 4: Molding the Torso

With the large size of the torso, I wanted to make the molding process as easy as possible. Two-part molds are, of course, the traditional, preferred method. But I like the simpler molding process of a one-part mold that covers the whole sculpt. Especially for something this big, and also considering my budget and schedule. Molding was really where I wanted to think more out-of-the-box and do it my own way.

Again, since the torso body form I had was hollow, all I would have to do is cover the clay with plaster, and then empty out the inside. The plaster part was easy enough, just brushing on the initial beauty coat, then adding more build-up, and also soaking plaster in a cut-up cloth canvas to give more strength. This was my first time using Ultracal for molding, as opposed to Plaster of Paris. Ultracal is so much stronger, nice to work with.

De-molding time! I figured it would be pretty easy, like my Batman mask. The sealing coat of Crystal Clear should be a fine release agent, right? Well, I didn't take into consideration the fact that my Batman mask was very smooth and clean. Unlike Cthulhu, which had all sorts of wrinkles, ridges, and bumpy textures. I'll just put it this way; it took me over 3 hours to empty all the clay out of the mold. I used no less than the following tools: my fingers, a toothbrush, a rag, a scratch pad, a knife, wooden spoons, water, a paintbrush, a garden hose, sculpting tools, a towel, and a toilet brush. As planned, I was able to save a lot of the clay from the sculpt. Recycling this clay was critical; I still had a lot of pieces left to sculpt. A lot of exhausting work, but would serve as a warning, recommending good adjustments for future molding. Though every piece I molded presented its own unique challenges.

Another point to raise was discovering how thin my molds were. Plaster molds are usually made to be at least an inch thick. To preserve materials, I was trying to stay at half and inch or so. Some spots on the mold were too thin, and many chips and holes were discovered. I was able to seal up these holes with joint compound. It was very hard for me to make a smooth, accurate, solid mold. I was learning first-hand how meticulous making a mold can be.

Important lesson learned: use stronger release agents, and wooden tools, for removing clay.

Step 5: Head

Following the traditional portrayals of Cthulhu, I built the head up as something of a large bulk with tentacles at the front (tentacles would be sculpted and molded separately). To ensure that I could see out of the costume, I positioned the eyes similar to my own. The sculpt was so large that face covered all of bottom of my own head, meaning I didn't have to sculpt anything beneath the chin, leaving a large hole on the underside, good for air circulation and breathing.

I had an idea in my mind of how I would mold the head. Ideas are powerful things. But a strong reality check is even more telling.

To save time, I didn't want to go through the effort of making a dividing wall with clay. So, I experimented; I made a plaster bandage shell of the back half of the sculpt. My idea was to then fill that shell with plaster, and lay the sculpt into it, having a perfect basin to fill up the back half to a smooth dividing line. But alas, the plaster was not as smooth and easy to use for filling in the space as I had wanted, and the whole thing made a mess. So I just made the whole thing a one-piece mold while I was at it.

This meant I would have to go through an intense process for emptying the mold, chipping away the Styrofoam head little at a time. And still a bunch of clay stuck in there. Eventually, I got it all cleaned out, and I did have a head mold.

Important lesson learned: don't try to take a shortcut by laying the sculpt in a shell of plaster. It doesn't seem to work.

Step 6: Legs

Sculpting was a similar process, random whims to guide my design. Which wasn't much for the legs, I kinda got bored with them, and just got to a point of "eh, that's good enough". So much for high quality detail. Whatever. It'll still look like Cthulhu in the end, right?

For the legs, I was determined to finally do a decent molding job. I took the time to make a dividing wall. And for easier release for the clay, I added some Vaseline and baby powder onto the sculpt. And I covered the first half in plaster. Moderate success. Flipped it over, sculpted the back side. Lubed up the edges of the plaster walls with Vaseline for a release, and I was ready to go. Back side molded. Ready to pry the two halves apart. Or not. Beyond the fact that I didn't make any pry points, the plaster was so thin that if I were to pull with a lot of force, it would likely break. And also, the plaster I put on dripped over the previous walls, drying hard and "locking" the two halves together. So I was stuck with a one piece mold.

Anyway, it wasn't too bad in the end. With the Vaseline and baby powder, the clay came out fairly easily this time, for once. The weight of the whole mold was only 30 pounds, very modest for something this large. But now I understand why you want a thick mold wall; for durability and for prying halves apart.

Important lesson learned: the edges of molds need to be clean so that mold halves don't lock together.

Step 7: Feet and Stilts

It took a lot of reinforcing the plaster forms to make the feet sturdy enough to stand on their own. I should have put more layers on while molding them. Anyway, more clay layered on, and random design.

Molding was fairly simple for the feet; they didn't need to be 2-part molds (nice and open on either end), and wider on bottom than on top so all excess plaster would run down and build up thicker. The shins were vertical, and not as easy to build up a thickness, but some cloth canvas made for strong walls. Cleanup was also smooth(er). And it was very nice to finally have some molds with a flat bottom that were easy to stand upright and work with.

Stilts are almost always made of strong wood pieces or metal. On a budget and schedule, I came up with a quicker and cheaper alternative. I did use a piece of wood for the main foot piece, but the rest was built up with foam boards and PVC pipe. Very cheap stilts. I nailed some old shoes onto the wood, and lots of hot glue for reinforcement. I also added some foam pads onto the bottom. They do support my weight, though like any digitigrade stilts, they are a little uncomfortable on the toes.

Step 8: Arms

More clay, more random sculpting.

To simplify the hands somewhat, I decided that I would sculpt the arm and hand without the fingers, and mold those separately. This would save me the time of having to sculpt several identical fingers, and going through the time of making a highly intricate dividing wall. A good consideration, because finally, I was going to make a good 2-piece mold for a body piece. Since the arm only had a hole on the shoulder end, completely enclosed on the other end, a 2-part mold was required.

So I built the dividing wall, and laid the plaster. Added some cloth pieces to reinforce and thicken the edges of the mold. So far so good. Onto the other side. I do the same thing. The edges all look good, just as planned. Then came the separation. Pulling the mold halves apart includes wedging something in between the edges and tapping lightly. The molds came apart, but not without problems; on both arms, one of the halves had severe cracks. Apparently I had made the molds so thin on the edges that when I pried them apart (with a hard metal screwdriver, not the best choice), the pressure was too much. I had to glue some pieces back together, and add extra plaster to reinforce the cracked areas.

But I wasn't done yet. When I tried putting the mold halves back together, I noticed they didn't fit too well; the prying I did with the screwdrivers bent the pieces a little bit. So, I decided to use some clay around the edges of the seam to help them seal together. When I cast the latex later on, I poured latex inside and sloshed it around, and none of it leaked out, so that was a good save.

Important lesson learned: there's a good reason for thick walls on plaster molds.

Step 9: Tentacles, Fingers, and Wings

For previous costumes, I'd made tentacles by dipping clay-sculpted forms into latex, letting it dry, and then peeling it off. For this, I wanted an easier method that allowed for more uniform castings, and also some surface texture, so I went ahead and made plaster molds off of 3 difference tentacles. It was much easier to make dividing walls and 2-part molds for smaller objects. Tentacles were sculpted out of clay, avoiding the traditional sucker pads, which I didn't want for Cthulhu. Looks a bit too much like an earthly animal.

The fingers were also made with the same process; sculpted 3 different finger designs, and made 2-part molds. An advantage to doing the fingers separately from the rest of the arm/hand was that I would only have to sculpt 3, and then I would simply recast multiple copies. Much easier than trying to sculpt 8 different fingers. 

The wings are large flat shapes, and so I needed a way to make gravity work for me rather than against me for my sculpting and molding. I decided to sculpt only one wing (to simplify and use less plaster), and do it in halves; I sculpted the design on a foam board, building up to as half as thick as it should be, and then molded that. Then flipped it over, removing the foam board, and revealing the clay on the other side. I had to sculpt inside the plaster edge line, but that wasn't too hard. After I'd build up the other half, molded that, and then had a nice 2-part mold that I could use to make 2 wings.

Step 10: Casting Latex and Assembly

The latex casting was a fairly simple process, especially compared to everything that had come before. Slightly thinned latex painted inside the larger molds with brushes, building up to a good thickness. I colored the latex green with acrylic paint for a good base color. Smaller molds, such as the tentacles and fingers, were filled with latex and then drained, leaving latex on the walls, usually built up in 2 layers. As I used up more of my latex, I was running low on the 2 gallons I had bought and needed more, so I used some old latex I had in storage. I noticed that the pieces I pulled from that latex were a bit weaker, and didn't seem as smooth. I bought more fresh latex to finish off with. It was definitely worth it; fresher latex is much better.

The wings were a unique challenge. Since I had one mold, with two non-symmetrical halves, and only a small open hole, I couldn't really do slush casting. I did try just in case, but it didn't quite work. Then I figured I'd just do halves, not a complete wing, just showing the good side forward. I built up about 6 or 7 layers on each side. But as I had latex built up in each half, I decided to join them together, and after a lot of patching and repair, I was able to make whole wings from two halves.

After pulling the latex pieces out, I'd wash them and scrub them clean. Sometimes there were little pieces of clay stuck on them, and also there was often residue of joint compound (that I had used to seal holes in the molds). For pieces cast from 2-piece molds, there would be a bit of extra flashing around the edge I'd buff off with a rotary tool (with a soft polishing bit).

Getting the difference pieces to fit together, with as little seam line as possible, was a bit tricky. Some pieces didn't fit together as well as they could have. The waist of the legs especially was way too big, and I had to wrap some excess material around and glue it together to make it more tight.  I used hot glue for the initial bond, and then sealed the seams with latex. Once I had enough latex on the seams, I was able to smooth them out, and for the most part, the joints were pretty smooth.

Down the back I had a zipper, which only went down half of the back, and was a bit difficult to get into the suit. To make the suit easier to get in and out of, I decided to cut the whole back open and put a zipper down the full length.

To keep the wings stiff, I added a wire from a coat hanger down the length of it. I then had a wooden dowel poking out the open end, and attached that to some PVC pipe. I added elbow pieces on the ends to leave two open sockets, meaning I could slip the wings into the holes in the back, attach the sockets together, and then zip up the back.

Step 11: Paint, Finger Mechanism, and Extra Details

For the shape of the hands and fingers of the costume, I thought it would be cool to have articulated fingers if possible. My thumb was in the same place as the suit's thumb, but I had a lot of extra room in the palm before the fingers of the costume. I'd seen before how to make a simple mechanism to pull fingers down, and luckily there was be enough extra room in the palms to allow my fingers to bend. The mechanism was made out of foam board for the main shape, and then duct tape to connect the tips of the costume fingers to my fingers, all hot-glued onto a glove. This slipped inside the arm, and then I added the fingers on top.

Paint was mostly green, to follow Lovecraft's basic description. Then most of the suit was just hand-brushed with acrylics (mixed with a little bit of latex), building up highlights and shadows, experimenting as I went. I added washes of very dark green for small texture details. Some spots of blue looked cool for extra emphasis, and flecking small specks of color added more realism.

I made eyes using clear plastic pieces from the packaging of a cheap dollar-store yo-yo. I painted onto those, keeping the pupils clear (so I could see out of them), and then super-glued them on. Clear coated those with some varnish, and also a resin coat to make them shiny and strong.

And one more interesting detail; I was at the grocery store one day and saw some crayfish. Only my sick mind would think "I wonder if I could use some claws and parts from those for details on the costume?". Surely enough, I was able to clean off pieces, saving the claws, legs, main body pieces, and even the eyes. Used sparingly, they were added on prominent places, like the eye ridges, the base of the "nostril" tentacles, wing tips, and fingers.

I sealed the costume with clear Plasti Dip spray. It's a great option for this, as it's clear, matte finish, easy to spray, and gives flexible protection.

Step 12: Cthulhu Rises!

Finally the time came to put the whole thing on.  In only takes a few minutes. First I step into the legs, and pull the waist up. Then I can either put on the stilts, or I can also just walk with my own feet. Then put the head on, slip the arms into the sleeves, have another person zip up the zipper and put on the wings.

Visibility out of the eyes wasn't too good, as the pupils were a little fuzzy from the clear coatings I added. Luckily, when I put the mask on, there was a small hole in the corner of the eye socket that I forgot to seal up that allowed me to see straight out of. I would later add another hole on the other side, which makes for a much better field of view. For most of the events I went to in the costume, I left the stilts off to make walking around and going up and down steps easier.

Audience reaction was pretty enthusiastic. Also, it turns out Cthulhu is truly terrifying; several small children ran away from me.

Step 13: Lessons Learned

Oh boy, what haven't I learned? I had performed all of these processes before on earlier projects, but never to this scale, and it was a whole different beast.

-I don't make designs. I build from designs. Those are two very separate things. As a result, the final Cthulhu only looks so-so. One of the reasons previous costumes like my Power Loader have been popular is because it's from a firmly established image, identifiable and iconic. I can build a Power Loader, sure, but I don't think I could ever create that design from scratch. Even at Stan Winston's effects house; there is a design team separate from the fabrication team.
-Lift with your legs. This is very sound advice. My back was aching a bit the first time I moved my torso mold with the clay inside. 
-Plaster molding is a complex task. There are good reasons for the established methods, from two-piece molds, to layers of burlap, to having a good thickness on the walls. Deviating from those traditions leads to great difficulties. It may be very particular, and tedious at times, but it's best to follow tradition.
-Speaking of plaster, the physics of air bubbles is something to learn about, and practice prevention. It isn't as simple as pouring plaster over your sculpt. You do need to be delicate, with your beauty coat and following layers, to ensure that all detail is captured, without air bubbles or thin spots.
-Overall, I'd say the most important thing for making a good sculpt, or mold, is patience. It takes time. It's not something you can take shortcuts on and expect the same result. The final product will only be as good as your mold is, and that's why it is such an important process with a lot of formal technique.
-Digitigrade stilts are tough on the toes. A lot of weight is down there, and so I have new respect for women who walk in high heels. Heh. But there are stilt designs that utilize straps and connections to the shins and thighs which help distribute the weight more evenly.
-The deadline I had set required me to schedule activities from day to day. I had to know what I needed to work on, and when it needed to be finished by. I planned out a whole calendar for the month, which always became more and more restricted as I procrastinated more and more.
-To be honest, while planning this costume, I imagined it was going to end up as something that looked really great, almost professional. The final product does look somewhat impressive, but going from impressive to professional is a huge difference. The precise details of sculpting, and also painting, are what can make a costume look great. And they take time, which I suppose I should dedicate more of in the future. I like the challenge of making something cheap and quick, but to increase quality, I may have to sacrifice more time to make it as good as it can be. 

To sum up, I got totally schooled in molding. I struggled the pressure of a time crunch. I executed an experiment in how little I could get away with. I learned a ton from the process, and understand more thoroughly the importance of patience and formalities. But in the end, I did have a costume, it was fun, and other people seem to have enjoyed it.

A breakdown of the final budget:

$100 Ultracal
$85 latex
$58 clay
$40 plaster strips
$6 cloth canvas
$6 brushes
$5 Plasti Dip
$5 paste wax
$5 random - plastic wrap and aluminum foil, containers, etc.
$4 rubber kidney
$3 crayfish
$1 eye pieces
Total: $318

This budget includes only the general  costs of materials I actually used for the costume. I may have bought more materials than I needed, so I did spend more than this. Despite my best efforts, I did not come under my $300 goal. Fairly close, but ultimately, the molds required more Ultracal than I had anticipated. All the molds I made together weighed about 140 pounds. Total time for construction was about 120 hours over the course of 4 weeks. It's easy to understand why costumes like these, professionally, can cost thousands,  and take months to make.

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    5 years ago

    You should use this method of construction for an Alien costume! It would look awesome.


    7 years ago

    Quick question how much clay was used for the torso section?


    Hi, Hun! Sorry for asking such a fundamental question. Did the WHOLE latex you used in the costume cost you only $85? Where did you buy it and how did you ask for it? Is it a special latex or how can I order it? My problem is, I live in Mexico, and market for latex is not too broad, so whenever I ask I only get "latex paint for walls".

    If you can help me it'll rock.

    This is amazing! I would like to see a "Call of Cthulhu" short film


    8 years ago

    Do u have to wear something specific under this? Or will everyday clothes work fine as well?

    Xombie Doll
    Xombie Doll

    8 years ago on Introduction

    I'm a huge Cthulhu fan and this is so awesome. You are so talented and creative, good work!

    that was awesome. i just finished the video. i can't believe you do most, if not all the work on your own, especially the own casting of your body.. that is hard core, but totally awesome. gives me some hope of one day working with latex


    10 years ago on Introduction

    can i buy liquid latex for costumes like this on amazon? I'm planning on making a man of steel costume so im wondering where i can buy liquid latex for a full-body suit like this.


    10 years ago on Introduction

    Congratulations on being a finalist in the Halloween contest!!! Can’t wait to see if you win! Good luck!


    10 years ago on Introduction

    That, Sir, ist a lot of work, but the outcomings are all worth the effort and price! superb costume for sure! :)


    10 years ago on Introduction

    This is awesome! I've never worked with latex before - I think I might have to after reading this. Fantastic costume, and thanks!

    I'm learning some mold making and casting right now, and have a small general tip: To remove water-based clay from plaster, get out what big chunks you can by hand, then soak the (fully cured and dried) plaster in a large container of water. Agitate as needed. Since the clay hasn't been fired, it dissolves right out (and dissolves faster with warmer water).

    This may not work as well if you're using the store-bought plaster of paris strips instead of cloth/burlap drenched in plaster, or if your mold is patched with joint compound (I don't know enough about joint compound to say). Perhaps that's why you didn't do it and I'm just going off on an unnecessary tangent :P

    But anyway, that could be solved by patching the plaster mold with plaster instead of joint compound.
    Time lost in the soaking of molds for both steps, but time gained in the swifter and hands-free removal of clay.

    Once again, awesome job, and thanks!


    10 years ago on Introduction

    Awesome costume!

    One question though ... why not dissolve the styrofoam head fill with acetone instead of chipping it away bit by bit?