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If you have any questions, you are always welcome to contact us. We'll get back to you as soon as possible, withing 24 hours on weekdays.
Customer service
All questions about your order, return and delivery must be sent to our customer service team by e-mail at yourstore@yourdomain.com
Sale & Press
If you are interested in selling our products, need more information about our brand or wish to make a collaboration, please contact us at press@yourdomain.com
For those who like to live dangerously and push beyond their mental comfort zone, the toughest collection yet has an added math challenge taking Su Doku to an even deadlier level of difficulty The seventh and toughest addition to the successful Times Killer Su Doku series will test puzzlers' skills to the limit, using the same 9x9 grid as normal Su Doku but with an added mathematical challenge. The aim is not only to complete every row, column, and cube so that it contains the digits one through nine, it is also necessary to ensure that the outlined cubes add up to the same number as well. With 150 new 'tough' and 'deadly killer' puzzles, there is no chance to ease in with easy puzzles.
⚠️ WARNING (California Proposition 65):
This product may contain chemicals known to the State of California to cause cancer,
birth defects, or other reproductive harm.
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