This is the second episode in the series. Playing the previous episode first is highly recommended.
Satoshi's Treasure is a multi-episode adventure map focusing on story, puzzles, and large-ish builds. Like typical adventure maps, you go around exploring places, killing monsters, collecting items, talking to NPCs, and unlocking the next part of the story. In addition there is a CTMish aspect where solving puzzles gives you Code Fragments. If you have all of the correct Code Fragments in the last episode then you can try to claim Satoshi's Treasure.
Episode 2 is moderately difficult. It can be completed in approximately 1.25 - 2.5 hours.
There are five episodes in total.