I have an idea, for a new resource called mud. If a block of dirt is under one water still block (If it's more it won't become mud) for more than 30 seconds, it will become mud.
It's like clay (It drops 4 mud balls) except it breaks faster. You can combine the mud balls to make the mud block. If you stand on the mud, you will sink into it like you will sink into soul sand, and move a lot slower as well. The mud balls can be thrown, dealing a half heart with each hit, and a chance of causing slowness 1 for 5 seconds.
A mud block can be smelted and turned into hard mud, which is like stone and a bit harder. You don't sink into it, and it's a great building material. If you smelt mud balls individually, they tun into mud bricks! The mud brick is as hard as brick.
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