The most recent March version update introduced the Voidwalker NM system to FFXI.
The Voidwalker NM or VNM System introduces a new way of popping NMs in Final Fantasy XI that involves the use of key items and /healing. This adds the element of tracking the mob down into a popped NM system. VNMs take a step further ahead of ZNMs by entirely removing the need for trigger items and relying on key items only.
Also, all NMs in this system can be popped in multiple zones, allowing for a different experience each time the NM is killed based on environmental factors.
If you spot any mistakes do let me know and I'll edit it asap. also if you have any info to add to it, please do
Feel free to comment as well. :)