EOLine
The first and most important step of the ZZ Method. It involves orienting all 12 edges such that they may be solved using only <R, U, L, D, F2, B2> moves, while simultaneously placing the line edges (DF and DB). After the EO part, the cube is reduced to <R, U, L, D, F2, B2>. After placing DB and DF, the cube is reduced to <R, U, L>. Sometimes, DL and DR are also solved before ZZF2L (3-gen F2L). This is known as EOCross. Most of the time, EOLine is treated as two steps -- EO+Line.
Step 1: EO
Look at the U layer, D layer, F face of the E-slice, and B face of the E-slice.
- L/R sticker -- bad edge
- F/B sticker
- U/D sticker on other side of edge -- bad edge
>=4 Bad Edges
Place four bad edges on F/B using <R, U, L, D, F2, B2> and then do a F/B quarter turn. Repeat until there are no more bad edges.
2 Bad Edges
Place one bad edge on F/B using <R, U, L, D, F2, B2> and then do a F/B quarter turn. Repeat with the >=4 bad edges rule.
Step two: Line
Place DF and DB (DL and DR for EOCross) in their solved positions using <R, U, L, D, F2, B2>.
