When the time-limited mode and leisure mode are cleared, the hidden level can be opened: the hidden level is divided into time-limited mode and normal mode, with a total of 48 levels. Some levels are branch lines, and some are difficult versions of ordinary levels (difficult version of ordinary levels: some things will not destroy you in ordinary levels, but they will destroy you in the difficult version of ordinary levels). Six hidden objects can be found in the branch channel: young doctor, old doctor (hidden 1-7), worm (hidden 2-8), gray clay (hidden 2-9, 3- 1, 6-5), square tile and rectangular tile (hidden 4- 1).