Practice
Medium technique
Claiming
When a digit's spots in a row or column all lie in one box, the digit is in that box on that line. Rule it out of the rest of the box.
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