Why can't the pig spirit reach the main world?

When the pig spirit enters the main world, it will become zombie, so the pig spirit cannot reach the main world.

Pig spirit barbarians come to the main world or a dead end, and after a while they will become "zombies" into zombie pig spirits.

If the pig spirit survives in the main world and the last place for more than 15 seconds, it will be "scared" to become a zombie pig spirit. And its equipment will remain, the only change is that its hostility to adventurers will disappear directly.

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Pig spirits are passive creatures that can be ridden. It rides on a saddle and uses a radish fishing rod to control its direction. When a pig dies, it will lose raw pork. If killed by fire (including enchanted weapons and flint), cooked pork will be dropped. Carrots can be used to attract and breed.

Cows shed their skins and raw beef when they die. If a cow is killed by fire, it will drop cooked beef, including flames, magic weapons and flint. Wheat can be used to attract and breed.