Based on a suggestion from a player, we have enabled "Shift + Left Click". Here is the summary of mouse clicks.
Summary of Mouse clicks
- Left Click - Toggle shading of a cell
- Left Click + Drag to shade multiple cells.
- Shift+Left Click - Mark a circle in the cell.
- Shift + Left mouse click + drag to mark circles in multiple cells.
- Right Click - Toggle marking a circle in the cell.