Curse of Leadening

This curse turns boots into “concrete shoes,” essentially the opposite of depth strider or frost walker. Instead of something obnoxious like slowing the player down on land, it simply makes it so the player sinks through water as if they were falling through air, like the metal cap in Mario 64 but if you could still drown. With this curse, you can only jump one block high underwater - you cannot swim, and with this curse you can no longer negate fall damage by landing in water. It can be combined with depth strider, and at DSIII the player moves underwater exactly as they move on land. I think this would be super cool and open up possibilities for parkour maps and mapmaking in general.