> Rather than fighting other players directly, he used a special ability to teleport them in front of a computer-controlled firing squad, which would immediately kill them.

He's doing that because he can't attack them. And they can't attack him either. it says:

> the victim has no chance to retaliate

They mean literally. If he was just attacking people who could attack him, in a zone where PvP is enabled, it wouldn't be called griefing.

Also someone in comments below says they have patched this stuff now. Legitimate behaviors don't get patched.