Start with equals
A one-cell cage gives its value directly. Use it to remove that number from the rest of its row and column.
AYE.GG / NUMBER FORTRESS
Balance every cage. Repeat no number. Climb all 50 floors.
Use each number once per row and column. A cage's numbers must make its small target using +, −, × or ÷. Keyboard: Arrow keys move · 1–6 enter · Backspace clears.
A one-cell cage gives its value directly. Use it to remove that number from the rest of its row and column.
A 6× cage in a 4 × 4 grid can only use a few factor pairs. Cross out combinations that would repeat a number in one row or column.
For ÷ and − cages, divide the larger number by the smaller or subtract the smaller from the larger. Cages never require negative or fractional targets.
Floors 1–15 use 4 × 4 grids, floors 16–35 use 5 × 5, and the final fifteen use 6 × 6. Every deterministic floor includes a complete solution replayed before publication; alternate valid solutions are accepted.
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