Keyhole First Two Layers
Keyhole First Two Layers or Keyhole F2L, also working corner, is a method that solves, normally, the first two bottom layers of the 3x3x3 cube.
You start, like in normal LBL from a cross, then you fill in three of the first layer corners. From that point you solve three of the middle layer edges using the empty corner position as the keyhole (use D-turns to move it to where the edge shall go and use R [U] R' or F' [U] F to place it). After three corners and edges are solved you compleate F2L by first solving the last corner and finaly the last edge using the normal LBL algorithm: R U R' U' F' U' F or the mirror F' U' F U R U R' depending on the current orientation of the edge.
An alternative way to do keyhole F2L is to use this order:
- cross (doesn't have to match centers)
- 3 corners
- 4 edges
- 4th corner
For that you will need three algorithms to solve the last pice depending on it's orientation:
List of algs...
