Naboko Lite (Sokoban)

Naboko Lite is the limited version of Naboko, a full featured clone of the classic Sokoban game. The goal is to push the boxes onto the designated squares without getting stuck.
The boxes can be only pushed, never pulled, and only one can be pushed at a time. It sounds easy, but the levels range from very easy to extremely difficult, some takes hours and even days to figure out.