No. Only the top disc of any stack can be moved. Reaching a disc lower down means finding somewhere for everything above it first, which is the core of the puzzle.

The buffer holds discs temporarily while you dig toward the ones you need. It is also how runs end — if the buffer jams full with discs that have nowhere to go, you are stuck, so use it deliberately rather than as a dumping ground.

Adding a box is usually stronger, especially for a colour you hold several of, because a completed box clears and returns space. An extra buffer slot only postpones the jam without solving it.

There are 28 levels, becoming progressively more layered as you go. There is no timer on any of them.