Minecraft 1.21 is the upcoming update for Minecraft, and it is expected to bring new features, biomes, and mobs to the game. However, there are different speculations about what the update will include, and some of them are just assumptions and suggestions from the community. Here are some of the speculations about Minecraft 1.21:

• Forests and Fossils Update: This update would primarily introduce one or two new forest biomes, or one new forest biome plus improvements to existing forest biomes.

• The Desert Update: This is a major Minecraft update that overhauls the Desert Biome and adds a lot of new content announced in Biome Vote.

• Horizons Update: This update was set to improve the skys and horizons as well as adding new blocks, items, and biomes. It includes new variants of the Sun & Moon.

• New Combat: The update is expected to enhance the combat with things such as new enchants like cleaving for axe, and make weapons have elemental effects like a poison sword.

• End Update: Minecraft 1.21 is expected to be the end update, as 1.9 was the update in which we received end cities and the rest of the end things.

It is important to note that these are mere speculations at the moment, and there is no official evidence yet about the new features and release date of Minecraft 1.21.