𧊠LITS Puzzle
Level 1
Level
LITS is a logic placement puzzle where your goal is to shade exactly four connected cells in each bordered region of the grid. The four shaded cells must form one of four specific tetromino shapes: L, I, T, or S. Every puzzle has a unique solution that can be discovered through pure logical deduction, meaning you should never need to guess. The challenge lies in satisfying all four rules simultaneously across the entire board.
Each bordered region on the grid must contain exactly four shaded cells forming a single connected group. These four cells must take the shape of one of the four allowed tetrominoes:
The 2x2 square shape (O-shape) is never allowed. All shaded cells across the entire board must form one single connected group. No two-by-two area anywhere on the board can be completely shaded. If two different regions share a border between their shaded cells, those two regions must contain different shape types. Identical shapes are not permitted to touch side-by-side.
On desktop, click any cell to cycle through three states: empty, shaded (dark), and marked with an X to indicate cells you are certain should remain unshaded. Click and drag to paint multiple cells with the same state for faster solving. Use keyboard shortcuts for quick actions: press R to reset the level, U to undo your last action, H to get a hint, M to toggle sound effects, and Enter to check your solution. On mobile devices, tap cells to toggle states and swipe across cells to paint. All buttons have a minimum touch target size for comfortable play.
Start by identifying regions where the shape placement is most constrained. Small or narrow regions often have very few valid tetromino placements, making them ideal starting points. Look for regions that border many others, as the no-identical-adjacency rule can help you eliminate shape possibilities by process of elimination. Remember that all shaded cells must connect globally, so avoid creating isolated shaded groups early in your solve. Use the X-mark feature generously to mark cells you have logically determined should remain empty. The no-two-by-two rule is a powerful constraint that can help you deduce many cell states even before you know which shape a region will contain. Working from the corners and edges inward is often an effective strategy. When stuck, the hint system can either correct a mistake or reveal a correct cell to get you moving again.
LITS Puzzle features unlimited procedurally generated levels. Each level number produces the same puzzle from a deterministic seed, so you can share level numbers with friends and compare solving approaches. Use the level selector to jump to any level from 1 to 999, or press the Random button to try a surprise puzzle. Progress through levels sequentially for a steady challenge, or skip ahead to find your preferred difficulty. The hint system is available when you need help without spoiling the entire solution.