Tap a colour button and that colour is removed from the top of every tube where it is currently the top item. You never move items between tubes — the only decision is which colour to fire and in what order.

Because each tap affects the whole board at once. Removing a colour exposes whatever was beneath it in every tube simultaneously, so the same set of taps in a different order produces completely different boards.

Look at what a tap will uncover, not just what it removes. A tap that clears fewer items but surfaces the colours you need next is usually stronger than one that clears more and leaves you with nothing set up.

There are 40 levels with a move budget on each, starting simple and escalating into boards that need real planning.