I wasn't sure whether to put this in the Level Building board or in my videos thread, so I decided to play it safe and just put it in my videos thread.
As you might not be aware, scrapping a level that you've worked hard on might be the right thing to do in the end. If you're trying to make your level fun but you can't unless you drastically change everything, then you may as well scrap it. Alternatively, if you run out of ideas but your level isn't as long as you anticipated it to be, scrapping it and using its challenges in future levels may also be a good idea. Even if you're spent a really long time making your level, don't be afraid to stop making it if it doesn't meet your expectations.
To prove my point, of the 12 custom levels I've released for MBP this year, there are another half dozen or more that I started but never finished. Here are some recordings of my three most complete levels that never made it to my level thread.
Scrapped Level 1: The Long Road Ahead
This level was made, as the title implies, to just be really long. It was scrapped when I realized that long levels aren't always fun.
Hours spent making what you see of this level: ~3-5
Scrapped Level 2: Marble Blast Headquarters
(You may want to fullscreen the video to see the Help Trigger text better.)
Here we have a level that was made in an attempt to mimic some old LE levels that tried to tell a story while you played the level. While the level is quite pretty looking (especially considering it doesn't use any custom textures), it was scrapped due to running out of ideas, and the gameplay simply not being that interesting.
Hours spent making what you see of this level: 20+
Scrapped Level 3: Duct Fan Framework
This level was started about two or three weeks before I was invited to the Platinum Team. Its main concept was to use duct fans in as many ways as possible. Unfortunately, as i soon discovered, there aren't that many uses of fans that haven't been done in other levels before. That's the main reason why this level got scrapped; the secondary reason is that I decided to devote most time I had with Marble Blast to PQ instead of MBP customs.
Hours spent making what you see of this level: ~4-5
Next time you have a level in the works that doesn't seem like it will be very enjoyable, don't be afraid to scrap it. You'll find yourself slowly improving at level design over time if you let yourself figure out what works in a level and what doesn't.
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