Entering the Shadowlands ...

Episode 4 of Commander Keen is not far from fascinating me. That's likely the game I played the most (excluding beta-tests of PPP Team productions), and likely the game I'd love the most to replay once again. Of course, I'd love that some people would once say that about Bilou adventures as well, and somehow I hope I can learn something from CK4 that would help me reaching that goal.

Si je reprends la carte de Commander Keen 4 et que j'y reporte les différents éléments, on se rend finalement compte qu'il n'y a que 2 niveaux "gratuits" (c.à.d. qui n'apportent rien au niveau de la quête). Autre élément intéressant, dès les 2 premiers niveaux passés, la quasi-totalité du reste du jeu devient immédiatement accessible. Et ces deux premiers niveaux peuvent être franchis d'une traite par le joueur habitué tout en servant d'introduction à la majorité des mécanismes du jeu pour les autres. Une chouette manière d'éviter les "tutoriels".

I think one interesting aspect of CK4 is its overworld. It's mostly a select-your-level menu, and your goal should be to focus on those levels where a Guardian of Wisdom is being held captive. Of course, you don't initially know where they are, so there's some exploration dimension. The overworld is large enough so that you'll rarely see more than 3 levels on screen, but small enough so that you can travel it end-to-end in something a dozen of seconds.
During some spare time, I lost some time plotting which levels contain what "quest items". Guardians to be saved (red wizzrobes), hints from Floating Princess Lindsey that ultimately guide you to the Mighty Foot of Travel which can take you to the Pyramid of the Forbidden -- the otherwise unaccessible level. The major item is the swimming suit, hidden in Miragia, the disappearing desert city, which unlocks access to the three islands. Only the Isle of Tar and Sand Yego are "free fun levels" where you've nothing to earn (quest-speaking), not even a lot of lives or ammunition. They're rather an extra challenge, with fun-but-dangerous elements.

Beside this "swim lock", there's two gate levels (villages) at the start of the game, that can imho be seen as the frontier between basic skill acquisition and real danger. Both can be zoomed-through by the experienced player (just move to the left, hop over some monsters or spikes and you're done). It's interesting to see how the novice player is even -guided- through the sandbox area either by a friendly slope or an open door vs. a set of spikes.

For the novice players, they're a great introduction to the basic mechanics of the games, in a free-exploration fashion. Poles, doors, shots, switches ... everything is there, except key gems. It's interesting to see that a sandbox works as well as a tutorial to that regard. Of course, Commander Keen does not learn new moves during the game (vs. Rayman) and his move set is nuanced (ultra-pogo jump or rope-hop-while-blasting-downwards being examples) rather than complex (vs. Yoshi's Island or Super Princess Peach -- complexity arising from the number of possible actions and negative rewards from doing the wrong action at the wrong time).

Tout qui a joué à un Keen sait qu'un niveau ne peut être visité qu'une seule fois par partie. Sortir d'un niveau sans avoir trouvé le secret qu'il contient, c'est perdre définitivement ce secret jusqu'à ce qu'on recommence le jeu. Evidemment, pour éviter de bloquer le joueur, les mages seront le seul moyen de sortir d'un niveau quand ils s'y trouvent. Ce ne sont donc que les indices de Lindsey et le méga-pied-transporteur de la pyramide de la lune qui pourraient être loupés. Mais le résultat, c'est qu'on aura d'avantage tendance à explorer les moindres recoins du jeu, là où, dans Super Mario 3-*, j'ai davantage tendance à filer vers la sortie dès que les choses se compliquent, entre-autres parce que je sais que je pourrait refaire ce niveau-là plus tard (avec un meilleur power-up ou un peu plus de vies ...). Pourtant c'est bien Keen 4 le "platformer" auquel j'ai le plus joué et celui auquel je serais le plus succeptible de refaire une partie prochainement ^_^

Through the Commander Keen series, levels can be completed only once in a game: you never re-enter a completed level. That means if you complete a level holding a secret without finding it, you won't have the chance to get that secret before you replay the whole game. Imho, this is a key component that puts the player in an explorative mood, while you'll rather play a SuperMario game trying to zoom to the exit as soon as you don't feel easy in the level. The overworld reinforce that explorative mood by being itself open (once you've complete the two gates level at the start, 11/14 remaining levels become immediately accessible).

The overworld of the next opus -- the armaggedon machine -- is much stricter, with virtually every level being a gate to something else. There's very little room for exploration, just sufficient alternate ordering between the tunnels/balls pair to allow the player who faces a challenge beyond his skills at one place to try something else somewhere else. I spot that the two "mission-less" levels of Commander Keen 2 are also the ones where important plot/gameplay hints are unveiled. I'll investigate that further on another time.