In Order to purchase gear in The Abyss players will need to spend Abyss Points. Players can gain Abyss Points by completing quests in the Abyss, Killing Players, Completing Objectives and also Killing Monsters. You can also gain Abyss Points from Killing Players outside of The Abyss. The fastest and best way to get Abyss Points is by capturing Forts and Artifacts.
Aside from items costing Abyss Points some items also cost Gold and Silver Medals. The Gold and Silver Medals can be earned from capturing a Fortress in The Abyss. The formula is said to be top 3 DPS dealers get Gold Medals and the 7 after that will get Silver Medals. The more Abyss Points you gain the more your rank will increase. Your rank has no effect on the gear you can buy but you can get extra cool perks with Abyss Rank. (More below)
When you spend your Abyss Points your rank will drop. However you should focus on buying your gear first, before worrying about your Abyss Rank. You can track your recent Abyss Point accomplishments by hitting "P" and clicking on the "Abyss" tab.
This tab will show you everything you need to know about your Abyss Points. Also there is a box at the bottom right of the picture titled "Abyss Rank" When you click this box it will bring up your servers Abyss Points Leaderboard.
Above is a picture of the Abyss Rank Leaderboard. The above picture shows you what is required in order to move up in Abyss Rank and each position. The positions are nammed differently for Elyos, of course, but the amount required and people allowed in that position are the same.
Now, you're probably thinking "Well what happens if two people get above 800,700?". If two people get above the amount required for the rank then the person with the most Abyss Points in all will get the rank. Since only one person can be that rank, the person that "should" be that rank but is behind him will be the rank below. The other tabs show you Individual Players for each faction as well as the Legions with the most Contribution Points.
The perks of having a high Abyss Rank are special skills that are available to you. Starting at Rank 5 you will get a unique ability to transform into a specific creature. Each rank above 5 you will gain more abilities you can use while transformed. In order to purchase the materials required to transform you will need to use Abyss Points.
Learn more about Transformation in The Abyss
The downside of being high Abyss Rank is you will lose more Abyss Points when you are killed in by a player or in The Abyss. The same works the opposite way. If you kill someone that is high ranked you will gain many more Abyss Points.