Ice is the second obstacle you’ll face, and it’s not fun. It’s not super-complex, but it’s certainly not easy to deal with as you go farther — or further — along the path.
Ice is pretty simple to destroy: it requires three matches with the color of the dot inside the ice block. However, ice doesn’t “hold” a dot inside of it; dots can slide along behind it. It can also be empty if there’s a block above it keeping dots from falling down. Ice takes one hit from balls, bombs, clouds, and gems. When you get to the trains, it can be hard to see an ice-encased train car, so look carefully.

Level 46: the three phases of ice — the uncracked phase, the one-hit phase (the top-left quadrant of the board shows four of these), and the two-hit phase (the bottom-right quadrant of the board shows two of these).
Strategy:
The ice strategy depends on how much you need to get and how it’s arranged. In general, I’d say to address it after anchors, because anchors can be dropped past it. However, if you ever have any ice without any dots inside of it, break that first. You can hit it with bombs, clouds, and gems. Gems are the easiest way to break a lot of ice at a time, if you’re lucky enough to be on a stage that has them. Erasers and color-bombs only deal one hit to ice, so be aware.
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