15 moves
A smaller cube appears to sit inside the corner of the big one.
Finished pattern0 of 15
Algorithm
Start from a solved cube. On a scrambled one these turns make nothing but a mess.
Run the same algorithm 3 times in total and the cube is solved again.
Each letter is one face, turned a quarter turn clockwise as you look straight at it. An apostrophe means anticlockwise, and 2 means a half turn.