First off when they spawn on a hill the water just stays there

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is this herobrines work?

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when it updates though it becomes normal

this can cause a lot of issues

1. Crops can be destroyed
2.  Causes the player to have a harder time scaling the hill/mountain
3.  Unnatural Terrain Gen 
4.  Villagers Because they are not real humans they can get stuck

these are only examples it can get a lot worse