## Sunday, May 28, 2017

### Pyraminx Crystal

Originally posted April 10-12, 2017 on the BudLCuber Google site.

Recently Roark mastered solving the Rubik's Cube. It is a method that uses The Move, aka Al Bob Charlie, aka Up Replace Down GoBack. He also learned the basic Up Replace Down 3-cycle for corners. And how to twist corners with a Double-ABC. And how to double swap corners with a Triple-ABC.

I got to thinking that he could use the skills he has learned to solve Pyraminx and Skewb puzzles. We haven't tried it yet.

Then I wondered about the Pyraminx Crystal. It was half solved already when I got it out of the closet. I finished it up but wondered what my whole solution involved. I found this note in my Solutions spreadsheet:

White corners; white edges; 4 of the next 5 edges; middle layer lower corners, then last of the edges of the bottom layer; middle layer upper corners; middle layer edges; last layer corners; last 10 edges.

That sounded very familiar. I tried it out. Yes. Very comfortable. As far as all the corners except the last 5 it is all a matter of just putting them in place, or using Up Replace Down to place them. All edges can be done with ABC (The Move). The last 5 corners can be 3-cycled using the Up Replace Down 3-cycle, or double-swapped using Triple-ABC. They can be twisted using Double-ABC. Using the ABC moves on the last layer corners scrambles a few of the middle layer edges, so if wanted, the middle layer edges can be left scrambled until the corners are all solved. Or, of course, my traditional methods for placing and orienting corners can be employed.

Solving it a couple times using the old strategy for the bottom part (white on bottom) and the revised method for the middle edges and last layer was educational. I didn't really like the part of solving 4 of the next 5 edges. I decided to try solving 4 of the 5 bottom middle layer corners instead. It was quite easy. Then using the working face I solved the corresponding edges that go below the corners. Then I solved the last of the 5 corners and inserted the edge. I liked it better for some reason than doing the edges before the corners.

My Current Favorite Method:
1. White Corners
2. White Edges
3. Four of the five Corners in the bottom half of the middle layer
4. The Edges that go below those Corners
5. The last Corner and Edge that go in the bottom half of the middle layer
6. The five Corners of the top half of the middle layer
7. The five Corners of the top layer
8. Remaining Edges