Add the sargasso

Adding sargassum would help to talk about the environment, give another ocean biome, and new blocks and mechanics.

Sargassum could have properties depending on its color level, such as copper, like black, cream, or copper-colored sargassum

Sargassum could have two layers: one like a carpet, and another that acts like cobwebs

Sargassum bricks could be created (a real proposal) by mixing soil, gravel, and sargassum

It could act like a plant; stepping on the carpet could allow you to walk on it for a limited time

Furthermore, sargassum is a very interesting fertilizer; they could experiment with it in crops

We could see sargassum drop fish that were caught in it or other items, thus increasing the chance of catching something

They could also add an achievement for cleaning sargassum from beaches

Finally, sargassum is very common during spring and summer, so it's not far-fetched.