Sashikabe
Shade a connected wall and leave L-shaped white islands.
Controls
Shade cells so all black cells form one connected wall with no 2×2 block. Every white island is a one-cell-wide L shape. Each island has a circle at its bend and an arrow at one leg end pointing to the bend. A number in the circle gives the island size.
Logic · Shading · Region · Grid
Brain training · PuzGo