I wouldn't really say this game has much exploring in it. Parts of it are open enough to give the impression of nonlinear exploration, but at any given time, there's pretty much only one thing you can (usefully) do, with only a few branches- all of which eventually return to the main game. (Unlike, say, Knytt, where you can get the ship parts in any order you like, and no major game mechanics are introduced after the game start. Or like Kaipuu, which only sets limits on the player based on what powerups they happen to have, and lets the player see potential objectives long before they're reachable. ...and like again the same for An Untitled Story.) Cave Story has the same sort of feeling of pseudo-openness, but it has a straight, conventional plot, so the feeling is more limited.
Actually, I think it would be neat to compare and contrast Knytt and Glum Buster. Or Knytt and any other game. Or Glum Buster and any other game. But now just Knytt and Glum Buster.
Knytt | Glum Buster |
No dialogue | No dialogue |
Totally nonlinear | Quasi-nonlinear |
Very basic game mechanics; remain constant throughout game | Each area has several new game mechanics |
Tutorial features text explaining game controls and mechanics | Brief graphics showing what the controls do; no explicit explanation of mechanics |
Collect several ship parts; needed to win | Collect 250-odd grins; nonessential |
Et cetera.