There are seven divisions for the CSR, with the first five having six tiers. These include Bronze, Silver, Gold, Platinum, Diamond, Onyx, and Champion. However, before players can be placed within a division they must first play ten matches in order to be properly placed.

How good is Diamond Halo 5?

In the overall scope of the game, for Arena and Slayer, I would say Diamond rank puts you in the top 20% of players and Onyx puts you in the top 10% of players.

What happened to Onyx Halo?

During the Human-Covenant War, Onyx served as the headquarters of the SPARTAN-III program and was the location of the massive, three-sided Onyx Conflict in late 2552. At the conclusion of the battle, Onyx itself disintegrated, only leaving the Dyson sphere in its core intact.