I realized its possible to 'practice' any phase in La Noche de Walpurgis by selecting the phase from the main menu, typing anything as the password and then right clicking.
Phase 3, the other side scrolling scene, is decent. Nice graphics, but unfortunately features no bosses or anything, its just a a matter of getting through all the enemies. While not that exciting on its own, its a nice addition in the overall package, though nowhere near as cool as phase 1.
Phase 4, the isometric section, consists of a couple of different screens. The first screen (the lava area) requires you to solve an incredibly fiendish puzzle to clear it. The final screen can only be accessed if you aren't in practice mode, though I saw a screenshot at HOL that gave away the password to it and I couldn't resist using it. The final screen is a more simple little puzzle, but delivers a great climax to the game. The best part of phase 4 is easily the graphics, especially the last screen which looks super cool.
In addition to phase 2, phases 3 and 4 also feature fully voiced Spanish dialogue which is impressive. Without a doubt though the best use of this is easily in the final scene, even though I don't understand the language the scene is incredibly cool and dramatic, but of course I don't want to spoil it here.
I am yet to progress at all on phase 2. I used every item in every way and still got nowhere, so I will need someone with Spanish knowledge to help me on that, I'm yet to receive any help on the computeremuzone forums also. It would be great to understand how to clear the phase, as clearing the game from start to finish would be fun.
Anyway, the game is brilliant, one of my favorite discoveries from the Spanish scene. Even the intro which has an entire disk dedicated to it is awesome. The game overall just puts the majority of other Amiga games to shame.
So why on earth didn't the developers get this published? Why release it as public domain? I'd love to discover the story behind this.