Description
Core Gameplay
Each core floor (the central part of a building) contains fifteen differences – the highest number in this series. You have 120 seconds. Correct taps add core blocks; incorrect taps remove 5 seconds. Complete the core to unlock the next level.
Level & Content Design
Twenty‑five levels, each featuring a different core element (lift lobby, stairwell core, utility core – decorative). Differences are extremely fine – e.g. different screw head types, shifted handrail brackets. No updates.
Visuals & Experience
High‑definition, almost CAD‑like line art with selective colour highlights. The zoom function is essential and works smoothly. The game is best played on larger screens.
Key Features
A “penalty shield” can be earned by finding five differences in a row without error (one shield per level). No hints available in standard mode; a practice mode removes the timer and penalties but does not count towards progression.
User Value
For players who demand precision and quick decision‑making. The high difference count provides extended engagement per level.
Usage Scenarios
Focused evening challenge, competitive timed runs with friends, or as a benchmark for personal improvement.





