Logic Masters Deutschland e.V.

Rules

1. Cave: Shade some cells so that all unshaded cells are orthogonally connected, and all shaded cells are orthogonally connected by other shaded cells to the edge of the grid. A circled cell cannot be shaded, and contains a number that's equal to the total number of unshaded cells that can be seen vertically and horizontally, including itself, where shaded cells block the vision.


2. Fillomino: Place some orthogonally connected regions in the grid. Two regions of the same size may not share an edge. If a cell belongs to a region, it contains a number that's equal to the size of its region; otherwise it is empty (i.e. doesn't contain any number).


3. Negation: A shaded cell's value is equal to the negative of its number. An unshaded cell's value is equal to its number.


4. Japanese Sums: Clues outside the grid represent the sum of values in each contiguous sequence of non-empty cells, in the order of appearance from left to right or top to bottom. Consecutive sequences must be separated by at least one empty cell.
   A '?' represents any digit from 0 to 9. For a multi-digit number, its first digit cannot be 0. For clarification, '?' may be 0 while '-?' may not.