How did Hypixel make it?

Thanks guys

PeliPartioIn Herobrine's Mansion, there was dialogue without pressing anything.
How?

Not every command has to be triggered by a direct interaction.
It's more than likely a plugin, if you are on the server, but if you happen to be playing the singleplayer map, there is a chance it's a testfor or execute command.

The odds are more likely it's a testfor considering the age of the map.

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