Foglets

Standard 4x4 sudoku rules apply: every row, column, and 2x2 box indicated by darker shaded lines must contain a complete set of the digits 1-4. Killer cages: digits inside cages marked by dashed lines cannot repeat and must sum to the number shown in the top left corner of the cage. Fog: Only part of the grid is visible. As correct digits are placed, the fog will lift, revealing more clues. It is not necessary to guess; digits can be placed correctly using logic with only the visible portion of the grid.