Tectonic

Standard Tectonic rules apply. Tectonic puzzles are played on a grid of cells. Every cell belongs to exactly one block. Blocks contain up to five cells and have their boundaries indicated by thick lines. The objective is to write a number into every cell such that adjacent cells have different numbers, and every block contains all the numbers 1 to n with n the number of cells in the block. All Tectonic puzzles have unique solutions that can be found without guessing.

Cells can be selected by clicking on them. Multiple cells can be selected by holding Shift while clicking. Numbers can be written to selected cells either by using the keyboard or the grey input buttons. Pencil marks can be written to selected cells by holding Shift while using the keyboard. To clear the content of all selected cells, press Backspace.