Aren't horses unable to swim though, so what if, hypothetically speaking, your house is on an island and you have to get there, passing other large bodies of water on the way. I'm just saying, taking that much time to build bridges and actually getting there is hard for those people that have jobs, or other activities. Adding some sort of easier method should be added. Possibly adding very, very expensive spawn eggs to the market. Hostile mobs eggs should only be allowed in the PVP arena though.
P.S. If horses are able to swim, completely forget the rest of my post.
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