In case you are thinking about WildStar, or just interested in watching a funny video where a team shows off their Raid mechanic.
https://www.youtube.com/watch?v=YbItL4qcugk
There is also a write-up on Massively discussing the Raid compositions and loot drops (http://massively.joystiq.com/2014/05/13/wildstar-unveils-the-details-of-raids/#continued)
Here is also a write-up on just how hardcore the raiding is: http://wildstarreport.com/2014/05/13/wildstar-raiding-devspeak-and-an-interview-with-lead-dungeon-designer-brett-scheinert/
* 20 or 40 man raids only
* Complex attunement process to get access to the raids
* Designed for a small percentage of the population (at least at launch)
Cheers.