Cosmos / Agastia
Six players, Five winners
You will want to do 4 million honors to get the blue chest in this V2 Fight. It drops decent weapons and its materials are used in several other core weapons such as Dark Opus. However, the raid itself can be slow if the next Guild War is not that element.
The raid has a unique mechanic: a bar with a pointer, where one end is red and the other is blue. The more the pointer leans toward red, the more damage Cosmos deals with basic attacks; the more it leans toward blue, the less damage Cosmos receives. The pointer moves toward red when you deal a hit of 3 million damage, and toward blue when you land 10 hits. If the pointer is all the way red or blue, you get wiped.
So you want the pointer to be in the middle or at least, near red as Dark can do a lot of hits, pushing to blue easier.
The Wiki’s Advanced Grid Page has a lot of setups that caters towards newbies and even more progressed accounts. If I had to pick one setup from these, I would recommend this setup for newbies