Hide yourself from players completely, even hacked clients won't know you're there.
This is because we intercept and modify packets so that the player client will have no single data about a vanished player unless it has the permission to do so!
Add the following to your pom.xml
<repositories>
<repository>
<id>ossrh</id>
<url>https://oss.sonatype.org/content/groups/public/</url>
</repository>
</repositories>
<dependencies>
<dependency>
<groupId>com.azortis</groupId>
<artifactId>protocolvanish</artifactId>
<version>@VERSION</version>
<scope>provided</scope>
</dependency>
</dependencies>
The placeholder repository can be found here. The download can be found here.