New Boot Enchantment: Stable Ground

This is a simple enchantment that reduces knockback based on enchantment level. I figured this would be pretty helpful for PVP, since you wouldn't knocked away as much from attacks, or for when a player is bridging or even just up high and something tries to knock them off, like a skeleton, zombie, or even player. It would go on your boots, and I'm thinking it could have up to 4 levels. Level 1 shaves off 25% of natural knockback, level 2 reduces 50%, etc. Level 4 gets rid of all-natural knockback. Knockback enchantments would still affect the player, but it might be a little weaker (I dunno, I haven't done the math...). I'm thinking since it's a fairly strong enchantment, it should be at least a little harder to get. Maybe it only spawns in a certain structure? Maybe a librarian villager very rarely trades for it? I'll leave it up to you, because that seems logical.