So, a few weeks ago, the programmer who helps Notch with Minecraft, Jens (@Jeb_ on Twitter) went on a twitter binge one night. He started mulling over pistons and a few other things. One of the things he came up with was a new type of block, a spiked block. One that can be pushed around with pistons, that deals damage to mobs/animals/players.
Unfortunately, the recently released terrain and item image files for the 1.7 update have been released, and no sign of a new block is in either file. I hope it still happens, but nothing more has been mentioned of it since this twitter ramble a few weeks ago.
For clarity, I've copy/pasted the pertinent tweets/replies about the new (hopefully) block. This conversation took place over June 7th through June 15th:
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@jeb_ Jens Bergensten
Yeah, I plan to include "sticky pistons," but I'm wondering what makes them sticky. Maybe they are not sticky, but spiky... and harmful...
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@charles_1597 Charles Duval
For the sticky pistons you could put a normal piston with a slimeball For a spikey one you could put flints all around a normal piston
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@jeb_ Jens Bergensten
Ah the flint suggestion is nice!
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@Terrormokes Jonathan McKeown
Will Spikey rams deal damage to mobs and things?
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@jeb_ Jens Bergensten
That was the idea. And deal more falling damage if you land on one. But @notch and me decided for something different...
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@0Nightfire0 Bob Ferree
Ohh! You could make a spiky block to be used with the sticky pistons. Same effect more options.
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@jeb_ Jens Bergensten
Exactly
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Chronaliz Derp Derpsen
About the sticky pistons. Will the spikes be a totally new block, that you can use as traps AND be able to be pushed by pistons?
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@jeb_ Jens Bergensten
I think that is the method we'll use, yeah
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