Product review (4 stars): Cute project for older kids, takes some coodination. Only includes four patterns and enough cubes to make them.
I was wavering between four and five stars, but settled on four because of the recommended age - four and above.  This is more like a toy for 6 and above - saying 4 and above is over ambitious. It takes a lot of coordination, accuracy and practice.  Picture a cross somewhere between a Light Bright and Lego's. Each cube is about 1/8". You need DRY hands, or the cubes stick to them. My GF took a while to assemble one design and at one point was using tweezers.

There are four patterns and enough blocks to make each pattern one time with no mistakes. Heck, one bag had just two cubes - I'm guessing eyes. You lay a pattern down on the grid thing (looks like a stop sign Lego base) and follow it with the cubes. Brown on brown, white on white and so on.  Expect to spend 10-15 minutes to assemble a pattern.

If you've seen Minecraft, you'll think "ooh, Minecraft models!"  Looking at these reminds me of the early days of video gaming - I'll bet that was the idea.

Anyway, assemble the pattern, spray with water - actually SOAK with water (25 pumps - about 20% of the bottle.) Spin for at least 30 seconds, then let it sit for at least 20 minutes.  Peel up and you're done. Some designs include extras, such as a weapon for the viking.  Younger kids will need help.

The cubes are water soluble, and I'm guessing they are corn based, but I can't find any details on the ingredients. For extra strength and durability, flip over and spray the back, then let sit overnight.

The spinning for 30 seconds seems to take forever. Surprisingly none of the cubes flew off.

You're also going to run out of cubes fast!  There are a variety of kits available. The instructions are good, but not great. Several of the usual English / Chinese translation errors.