Creativity: 3.5/5: Making it untargatable at the same time as you make it unable to act is very creative, still it is based on something that already exist
Theme: 5/5 Crystallizing something makes it harder to destroy, so theme is coherent
Execution: 4.5/5: Maybe I am biased, but I dont see any reason not to take +++ over the others, even if it is more costly being able to target 4 more squares (being the most important the front one) makes +++ so much more apealing than any other from a cost/efficiency point of view, other than that values seem okey, being the one from + to ++ maybe a bit exagerated (4 cost just for axial move or atack), but taking into acount the future kingmovers nerf it makes sense.
Even if I give it a 3.5 in creativity (because of it being based on freeze/petrify), I thing the concept of this piece is really good, good job!