All 6 games are implemented! You need to have JRE >= 8 installed. Then simply invoke the jar file and Merlin appears as we would live in the good old 1970s. To start a game click "New Game" and then 1 to 6.
The original user guide can be found here: https://archive.org/stream/manuals-handheld-games-ParkerBros-Merlin/ParkerBros-Merlin_djvu.txt
A right click in the Merlin window also shows the user guide.
