Practice
Champion technique
X-Wing
When a digit fits only two cells in each of two rows, and they share the same two columns, the digit takes one corner of each column. Rule it out of the rest of both columns. The same works with rows and columns swapped.
1FocusOnly what mattersNext
Start2Notes givenFull grid, notes filled inLocked
3Your own notesFull grid, you make the notesLocked
4Against the clockHow many in a row?Locked
5 right in a row passes a level