Avalanche - connection
It is, however, also an excellent joseki in its own right. Players of any level of knowledge can play this move whenever they feel that taking territory in the corner in exchange for giving White influence in the center is not disadvantageous.
is more or less the only move, and is the most usual continuation. After that, White will usually fix up her shape with a. Other plays for White are: lengthen the wall with b, play tenuki, or play at c to try to force Black.
is not absolutely sente, but if black does not answer, white forces with to to take control of the corner.
If Black omits , White might play there, and Black is more or less obliged to play a, which is painful. can also be played at b.
If white plays tenuki, is a tasking move. It is not the most common one, but we are going to gloss over at a, which leads to complicated fighting needing many diagrams and , which reverts to the joseki shown above. White keeps black separated, then pushes against the black corner group. This gives black territory, but white makes strength, thus weakening the -- stones. A white counterattack against these is likely to follow soon.