The full logical solve of the hard LITS for September 22 to September 28, 2026, 10 × 10. 42 steps, 6 techniques, no guessing. Step through it, or jump to any step below.
Every tetromino that still fits in this region covers r3c7, r3c8 and r4c8.
Every tetromino that still fits in this region covers r5c10.
Every tetromino that still fits in this region covers r4c1 and r5c1.
Every tetromino that still fits in this region covers r3c5, r3c6 and r4c6.
Every tetromino that still fits in this region covers r4c3 and r5c3.
Every tetromino that still fits in this region covers r7c6, r7c7 and r8c6.
Every tetromino that still fits in this region covers r8c2, r9c2, r9c3 and r10c3. Only one fit is left: an S.
Every tetromino that still fits in this region covers r9c7, r9c8 and r10c8.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r1c9.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r3c4, and none covers r4c7. Only one fit is left: an L.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r2c2, and none covers r2c5.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r5c6 and r5c7, and none covers r4c4 and r4c5.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r6c2, r7c1, r7c2 and r7c3, and none covers r8c1, r8c3, r9c1, r10c1 and r10c2. Only one fit is left: a T.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r3c1 and r5c2, and none covers r6c1. Only one fit is left: an L.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r2c3.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r1c5 and r1c6, and none covers r1c1 and r1c2.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r5c4 and r6c4, and none covers r4c2 and r6c3. Only one fit is left: an S.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region misses r6c5 and r10c7.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region misses r8c7.
Fits that would touch a tetromino of the same shape next door are out. Every fit left in this region covers r2c1 and r2c4, and none covers r3c2 and r3c3. Only one fit is left: an I.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region misses r1c3.
Fits that would touch a tetromino of the same shape next door are out. Every fit left in this region covers r1c7 and r2c6, and none covers r1c4. Only one fit is left: a T.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r4c9, and none covers r2c7. Only one fit is left: an S.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r1c10, and none covers r3c9.
Fits that would touch a tetromino of the same shape next door are out. Every fit left in this region covers r1c8 and r2c8, and none covers r2c9. Only one fit is left: an L.
Fits that leave a neighbouring region no tetromino that works beside them are out. Every fit left in this region misses r6c8.
Fits that leave a neighbouring region no tetromino that works beside them are out. Every fit left in this region covers r9c5, and none covers r7c5.
Fits that leave a neighbouring region no tetromino that works beside them are out. Every fit left in this region covers r10c9, and none covers r9c6. Only one fit is left: an S.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r8c10, and none covers r9c9.
Fits that would cut some shading off from the rest are out. Every fit left in this region misses r6c10.
Suppose r5c5 is left white. Following the rules from there, a region would have no tetromino that fits. So it is shaded.
Fits that would touch a tetromino of the same shape next door are out. Every fit left in this region misses r6c7.
Suppose r6c6 is left white. Following the rules from there, a region would have no tetromino that fits. So it is shaded.
Every tetromino that still fits in this region misses r5c8.
Suppose r5c9 is left white. Following the rules from there, a region would have no tetromino that fits. So it is shaded.
Every tetromino that still fits in this region misses r2c10.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r6c9 and r7c9, and none covers r3c10 and r4c10. Only one fit is left: an L.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r9c10.
Fits that would touch a tetromino of the same shape next door are out. Every fit left in this region covers r7c10 and r10c10, and none covers r8c8 and r8c9. Only one fit is left: an I.
Fits that would touch a tetromino of the same shape next door are out. Every fit left in this region covers r8c5, and none covers r7c8. Only one fit is left: an S.
Fits that would finish a 2×2 block of shading are out. Every fit left in this region covers r10c5 and r10c6, and none covers r7c4 and r8c4.
Fits that would touch a tetromino of the same shape next door are out. Every fit left in this region covers r10c4, and none covers r9c4. Only one fit is left: a T.