Light Up (Akari)

Einstein Light Up is the hardest level: a 14×14 grid with only 15% wall density and roughly 20% of walls numbered. These puzzles are certified to be solvable by pure constraint propagation — no guessing or trial-and-error is required.

With nearly 200 open cells and very few numbered walls, you work primarily from visibility constraints and corridor isolation. The solution path requires layering multiple constraint types simultaneously: wall deductions, visibility exclusion, corridor analysis, and cross-grid propagation chains.

These puzzles reward methodical solving over speed. Work from the most constrained areas outward, propagate every deduction fully before moving on, and trust the logic. Also see the hardest puzzles page for more einstein-level challenges across all puzzle types.