You complete LITS when each region contains one valid LITS tetromino, all shaded cells connect orthogonally, identical neighbouring tetromino types do not touch, and no black square forms. The full LITS position determines the outcome; visual shortcuts never replace the documented LITS terminal rule.
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You complete LITS when each region contains one valid LITS tetromino, all shaded cells connect orthogonally, identical neighbouring tetromino types do not touch, and no black square forms. The full LITS position determines the outcome; visual shortcuts never replace the documented LITS terminal rule.
Complete guide
LITS uses the independently implemented Nikoli LITS rules v1 profile (R361). LITS is a complete deterministic browser game built around one shaded L, I, T, or S tetromino in every region, a connected global shade, no equal shapes touching across borders, and no black two-by-two block.
LITS begins with a clue-free grid partitioned into irregular regions, each large enough to contain at least one legal four-cell tetromino. The LITS deal identity and Nikoli LITS rules v1 are stored together. Restarting LITS reproduces this opening exactly.
During LITS, you shade cells to choose exactly four connected cells per region and may clear choices while the engine checks tetromino shape and global constraints. The LITS engine rejects profile violations, unavailable material, and every action attempted after LITS reaches a terminal result.
You complete LITS when each region contains one valid LITS tetromino, all shaded cells connect orthogonally, identical neighbouring tetromino types do not touch, and no black square forms. The full LITS position determines the outcome; visual shortcuts never replace the documented LITS terminal rule. In the LITS endgame, link the last shaded components without creating a two-by-two block and confirm adjacent regions do not share the same normalized type. Check every remaining LITS action before committing because its terminal rule is enforced immediately.
A reliable LITS plan is to enumerate feasible tetromino placements in the smallest regions and use required global connections to eliminate isolated candidates. A LITS hint is legal and deterministic. The next LITS hint exposes one bounded action; it never claims a forced LITS win. A costly LITS mistake is to treat rotations and reflections as different letters; shape identity is normalized before the no-equal-touch rule is evaluated. Undo supports studying that LITS decision, while restart preserves the original seeded LITS opening.
LITS uses one shaded L, I, T, or S tetromino in every region, a connected global shade, no equal shapes touching across borders, and no black two-by-two block. That rule belongs to the LITS engine and storage identity rather than a cosmetic preset.
Every region contributes exactly four shaded cells forming one L, I, T, or S tetromino; other tetromino shapes are never legal.
LITS records its game ID, rules version, and seeded deal identity. Those LITS values recreate the same opening without a server request.