From WPC unofficial wiki


Shade some empty cells so that shaded sections form squares and a number in a cell indicates the total of the areas of the squares touching that cell by a side. All white cells must form a single connected area. Cells with numbers remain white.

(Rules and example from WPC 2017 IB)

History of the puzzle[edit]

First appeared on Nikoli volume 123 (2008). Invented by あるかり工場長 (Alkali Kojocho). Mochikoro comes from "mochi" + "colony" in Japanese.

Appearances in the past WPCs[edit]