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Create A Castle BuildMaster Indoor Mystery Bag is a single mold kit for indoor sculpting using .9 lbs of CastleMagic sand. The kit includes a random custom mold, locking key, dimension forming tops, and a resealable storage bag so the compound does not dry out. Free how to videos are available.
Key Features
- Includes one random custom mold to build with
- .9 lbs of CastleMagic sand included in each kit
- Includes one locking key and one dimension forming tops
- Resealable storage bag prevents compound from drying out
- Based on award winning 2020 Toy Of The Year outdoor technology
- Free how to videos with molding and sculpting tips
- Play for minutes or hours from the comfort of your home
- Collect all 6 mystery molds to expand play
Details
- Brand: Create A Castle
- Product: BuildMaster Indoor Mystery Bag
- Contents: 1 random custom mold, .9 lbs CastleMagic sand, 1 locking key, 1 dimension forming tops, storage bag
- Storage: Resealable bag for sand when finished to prevent drying
- Technology: Based on award winning 2020 Toy Of The Year outdoor technology
- Extras: Free how to videos
How to Use and Care
- Use molds and CastleMagic sand to form castle parts
- Store sand in included resealable bag when finished to prevent drying
- Watch free how to videos for molding and sculpting tips
Who It Is For
For indoor sculpting play at home. Suits parents and children who want creative indoor activity based on outdoor play technology.
Frequently Asked Questions
What is included in the BuildMaster Indoor Mystery Bag?
Each kit includes one random custom mold, .9 lbs of CastleMagic sand, one locking key, one dimension forming tops, and a storage bag.
Will the sand dry out after use?
The included resealable storage bag prevents the compound from drying out when finished.
Are there instructions or tutorials?
Free how to videos are available to show how to mold and sculpt using the proprietary sand.
How long can children play with it?
You can play for minutes or hours from the comfort of your home.
Can I collect different molds?
Collect all 6 mystery molds to expand play.
All orders are processed and shipped within a maximum of 2 to 5 business days. Please note that this is an estimated timeline and does not constitute a guarantee, as national holidays and other external factors may impact final delivery and shipping times.
🚚 Free Shipping and Discount Clarification
For qualifying orders of $100 or more, the maximum available discount applied to your order is $30.
CastleMagic sand stays pliable and captures fine details so sculpted towers and stairways look real. The compound tears and reforms easily, perfect for build, smash, and repeat play.
Each kit includes a custom mystery mold, a locking key, and dimension forming tops to make three-dimensional castle parts. Watch our free how-to videos for simple shaping and carving techniques.
When playtime is over, stash the sand in the resealable storage bag to prevent drying between sessions. Build single parts or combine multiples, then pack away until next time.
Pick the kit that matches the play style, cleanup needs, and how long you want the activity to last.
- Play surface: Use a tray, placemat, or low table to contain sand and make cleanup much easier.
- Cleanup needs: Choose kits with a resealable bag and no-dry compound so you avoid daily disposal and vacuuming.
- Type of molds: Detailed molds are great for display pieces, while simpler molds encourage more open-ended sculpting and creativity.
- Tools included: Kits that include shaping tools, keys, and forming tops let kids learn sculpting techniques faster.
- Gifting and collecting: Mystery molds make collecting fun, add multiple bags for group play, parties, or large multi-part builds.
What comes in a Create A Castle BuildMaster mystery bag?
Each bag includes one random custom mold, about .9 lbs of CastleMagic sand, one locking key, one dimension forming tops, a resealable storage bag, and access to free how-to videos.
Will the sand dry out between play sessions?
No, the included resealable storage bag prevents the compound from drying out when stored properly, so you can reuse it again and again.
Can I combine parts to create a bigger castle?
Yes, you can build single parts or combine multiple parts to make larger structures, then rebuild or smash and start again.
How long does shipping take and what if I need a return?
We ship from a US warehouse, and standard US orders ship free when your cart is over $100. We accept returns within 30 days, and our human customer support team will help with any questions.
Is this product safe for younger children and pets?
Supervision is recommended, especially for very young children and around pets. Keep the compound away from mouths and follow any warnings on the package.
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G 5.0 on Google · 9 reviews · Verified buyer reviews from our store
"We got floaties for our toddler and they are great! She loves swimming and these are so nice to have. Company is owned by a husband and wife and they are kind and…"
"I purchased a bat costume for my daughter with Moogco and we absolutely loved it! We used it for our daughters first Santa photos. They are a small business worth…"
"Ordered from here and they sent my items fast! Great quality!"
"High quality toys. Customer service is helpful and responsive. Will buy from this store again!"
"All of my dealings with them have been great!"
"Wonderful company to work with! Great product"
"great prices and fast shipping!"
"Wonderful products"
"I was lucky to find this pad for my grandson’s bassinet. I like how it is all natural snd organic. Just make sure to buy it a little bigger because it shrinks after washing. Also give ample time…"
"These helped at first but it seemed like the edges dug into my skin making it irritated (might have needed the larger ones). Once my milk came in more, milk would spill everywhere. I found that milk…"
"Perfect. Great price and my little one very opposed to training has only had accidents in the last week. My daughter is 2yrs old, 27 lbs and the Medium is perfect. She has room in them but the arent…"
"Initially, I was skeptical of using it, but when my doc referred it to me for my cracked nipple, it worked like a charm. I did not want to put any balm or lotion over my nipple as I did not wanted…"
"Amazing tool for breastfeeding! These protect sensitive, chapped or cracked nipples like little shields. No more sticking to clothing/bras and wincing when anything bumps into my chest. I've been…"
"I cant belive they heal hours within you put them on. Totally a must while breastfeeding. Such a good quality"
"I used these for the first four weeks after baby came. It was during that phase where baby was so small he didn’t have a great latch and so I was getting sore nipples. This was great for protecting…"
"Only paci my breast feed three week old has accepted so far🙌🏼"
"Worked great and would definitely use again. The only thing is sizing can be tricky. I would’ve gotten a size bigger and I’d consider my size to be on the smaller side. If you’re not sure, just size…"
"I wore these for the first two months and they truly saved my breastfeeding journey - worked exactly how I expected. They gave instant relief. I basically wore them day and night for the first 6…"
"Love these , I bought due to damage from pumping . One week with creams and balms didn’t do much but two days with these and I’m almost healed !"
"LIFE. SAVER. Bought this the first week I started nursing my son and had the WORST cracked nipples. These solved the issues OVERNIGHT!"
"I was lucky to find this pad for my grandson’s bassinet. I like how it is all natural snd organic. Just make sure to buy it a little bigger because it shrinks after washing. Also give ample time…"
"These helped at first but it seemed like the edges dug into my skin making it irritated (might have needed the larger ones). Once my milk came in more, milk would spill everywhere. I found that milk…"
"Perfect. Great price and my little one very opposed to training has only had accidents in the last week. My daughter is 2yrs old, 27 lbs and the Medium is perfect. She has room in them but the arent…"
"Initially, I was skeptical of using it, but when my doc referred it to me for my cracked nipple, it worked like a charm. I did not want to put any balm or lotion over my nipple as I did not wanted…"
"Amazing tool for breastfeeding! These protect sensitive, chapped or cracked nipples like little shields. No more sticking to clothing/bras and wincing when anything bumps into my chest. I've been…"
"I cant belive they heal hours within you put them on. Totally a must while breastfeeding. Such a good quality"
"I used these for the first four weeks after baby came. It was during that phase where baby was so small he didn’t have a great latch and so I was getting sore nipples. This was great for protecting…"
"Only paci my breast feed three week old has accepted so far🙌🏼"
"Worked great and would definitely use again. The only thing is sizing can be tricky. I would’ve gotten a size bigger and I’d consider my size to be on the smaller side. If you’re not sure, just size…"
"I wore these for the first two months and they truly saved my breastfeeding journey - worked exactly how I expected. They gave instant relief. I basically wore them day and night for the first 6…"
"Love these , I bought due to damage from pumping . One week with creams and balms didn’t do much but two days with these and I’m almost healed !"
"LIFE. SAVER. Bought this the first week I started nursing my son and had the WORST cracked nipples. These solved the issues OVERNIGHT!"
"We got floaties for our toddler and they are great! She loves swimming and these are so nice to have. Company is owned by a husband and wife and they are kind and…"
"I purchased a bat costume for my daughter with Moogco and we absolutely loved it! We used it for our daughters first Santa photos. They are a small business worth…"
"Ordered from here and they sent my items fast! Great quality!"
"High quality toys. Customer service is helpful and responsive. Will buy from this store again!"
"All of my dealings with them have been great!"
"Wonderful company to work with! Great product"
"great prices and fast shipping!"
"Wonderful products"
"Did the job, kept me more comfortable the first couple weeks postpartum as breastfeeding was established. Next time I would go for the design that has perforated holes for airflow."
"As a breastfeeding mom I truly couldn’t recommend these more. They literally SAVED MY LIFE in the newborn stage and then saved me again when teething started. They’re easy to use, easy to clean and…"
"This is a great item to have for breastfeeding mommas. It feels very cooling and refreshing after breastfeeding and makes wearing nursing bras very comfortable since the fabric is not rubbing on your…"
"These cups protect and help heal sore nipples so quickly. Comfortable under a bra, easy to clean, and worth the investment for breastfeeding. Stats: 5’3”, 140 lbs, 8 weeks postpartum & nursing"
"Great value for the price compared to name brand silverettes. I only really used them for maybe 2-3 weeks, so I’m glad I didn’t spend the extra money when these got the job done just as well"
"These are perfect for breastfeeding. They help keep any ointment or lanolin from getting on your clothes and smooth for immediate relief of cracks or nipple soreness in the first few weeks."
"Had a cracked nipple, added some organic ointment and put this over it, healed in 2 days! Recommend it 100%"
"These are great for nursing in the first few weeks when there’s soreness and breakdown. Would recommend!"
"These were wonderful for me postpartum while learning to breastfeed. Highly recommend. They are easy to clean & very functional."
"It saved my nipples multiple times. They’re super light. Quality is good, they do bend for no reason lol overall a good product."
"These were great in the beginning helped me so much."
"Any first time mama BUY THIS PRODUCT!!!! I cannot recommend and rave about this enough. They HELPED so so much! I wore them all the time when my nipples felt dry, cracked, and just hurt. Those first…"
"Did the job, kept me more comfortable the first couple weeks postpartum as breastfeeding was established. Next time I would go for the design that has perforated holes for airflow."
"As a breastfeeding mom I truly couldn’t recommend these more. They literally SAVED MY LIFE in the newborn stage and then saved me again when teething started. They’re easy to use, easy to clean and…"
"This is a great item to have for breastfeeding mommas. It feels very cooling and refreshing after breastfeeding and makes wearing nursing bras very comfortable since the fabric is not rubbing on your…"
"These cups protect and help heal sore nipples so quickly. Comfortable under a bra, easy to clean, and worth the investment for breastfeeding. Stats: 5’3”, 140 lbs, 8 weeks postpartum & nursing"
"Great value for the price compared to name brand silverettes. I only really used them for maybe 2-3 weeks, so I’m glad I didn’t spend the extra money when these got the job done just as well"
"These are perfect for breastfeeding. They help keep any ointment or lanolin from getting on your clothes and smooth for immediate relief of cracks or nipple soreness in the first few weeks."
"Had a cracked nipple, added some organic ointment and put this over it, healed in 2 days! Recommend it 100%"
"These are great for nursing in the first few weeks when there’s soreness and breakdown. Would recommend!"
"These were wonderful for me postpartum while learning to breastfeed. Highly recommend. They are easy to clean & very functional."
"It saved my nipples multiple times. They’re super light. Quality is good, they do bend for no reason lol overall a good product."
"These were great in the beginning helped me so much."
"Any first time mama BUY THIS PRODUCT!!!! I cannot recommend and rave about this enough. They HELPED so so much! I wore them all the time when my nipples felt dry, cracked, and just hurt. Those first…"