This datapack (and its mod ports) introduces a single condition-based change:

When a horse is equipped with leather horse armor, it becomes able to walk on powdered snow blocks without sinking.

All mechanics described below apply only when using this datapack (version 26.1.2). In vanilla Minecraft, powdered snow has no special traversal rules — you simply sink into it, and no alternate behaviors or edge cases apply.

When the datapack is active, powdered snow behaves more like a constrained surface rather than a normal block. You can jump from a solid surface onto powdered snow, and you can also jump between powdered snow surfaces, including onto higher powdered snow blocks if positioned correctly.

However, you do not “step up” onto the surface like you would with normal blocks. Instead, entering it directly causes you to be slowed down just like walking in powdered snow in vanilla, and once inside, jumping is no longer a way to regain height or escape. This creates a clear distinction between jumping onto powdered snow versus walking into it.

You should instead always jump onto a higher surface and never walk into it.

I also noticed a little quirk: if you are inside powdered snow and move directly into a solid wall, the game may cause the entity to be pushed upward onto the powdered snow surface. This behavior does not appear to be intentional, and should not be relied upon for movement or traversal outside of version 26.1.2.

In multiplayer, the datapack only needs to be installed on the server, and all players will experience the effect normally.

Important: Horse-like mobs added by other mods are not supported, and may not receive the intended behavior depending on how they are implemented.

Compatibility with other Minecraft versions is likely, but not fully tested yet.