The ShengShou 4x4 Pentahedron is a very interesting puzzles and shows ShengShou have decided to further pursue their pentahedron line, a line which I expressed my surprise it had not been done before when they first released the 2x2 and 3x3 pentahedron puzzles. The 4x4 pentahedron was quite a challenge as I had to work off my base knowledge of centre building and edge pairing from big cubes but the space to store solved edges was simply not there, it just would not work in the same way, I eventually just randomly solved the centres. After a fair amount of messing around I figured out a way of pairing up the edges on the top and bottom using a similar technique to 5x5 edge pairing, however, to solve the final middle layer edges was far more challenging and I eventually resorted to the instruction pamphlet inside. The 3x3 stage was far more frustrating than I expected as the colour scheme was messed up a bit and there may have been some parity cases, after a lot of frustration I did eventually solve it and I would recommend it as a great puzzle to try! You can buy it here.