Triangles

There are some effective rules that involve recognizing some roughly triangular configurations.

The 1-1, 2-2, and 3-3 Triangles

All highly similar -- though only the 3-3 Triangle gives you mine locations, all three indicate the same three squares are clear:













The 1-2 and 2-3 Pyramids

These particular shapes are more common than you might think, and give you three clear squares, once you learn to recognise them. The 1-2 Pyramid gives you three clear squares:








The 2-3 Pyramid gives the same three squares, with the bonus that if the middle cleared square is a 1, you can clear the yellow squares as well: