Imho MSX library is a little thin on games in the maze / exploration / adventure genre. Read: where wandering around is a prime (if not the) feature of playing the game.
For comparison: I remember from my ZX Spectrum days games like Roller Coaster where you'd explore a theme park (with many elevators, ferris wheel, carts etc), Knight Lore, Scuba Dive, Terminus, Avenger, and many more where you'd have vast worlds to explore, items to collect, and enemies to slash. The Sokoban style maze-puzzler Thunderbirds (not the Grandslam one!). Or the mazes in Maziacs that would be auto-generated & therefore different each run. Yeah I know some of those titles have MSX version...
What do you consider the best virtual game worlds that exist for the MSX, and why? "Best" as in: largest, most interesting, most beautiful, most fun to explore, most unique theme / layout / behaviour / items in it, etc? For all I care you can include other games like shoot-em-ups where you think the map / graphics design warrants a special mention.
Any ideas to take the "MSX state of art" in this area a step further?