Aion’s Stigma System is a feature which gives players the ability to further customize their characters by allowing them to equip special “Stigma Stones”. Each Stigma Stone grants a particular ability unique to that class. For the lore buffs out there, you can take relief in knowing that each Stigma stone carries the memory and strength of one of your fallen number.  Stigmas help distinguish you from other members of your chosen class by granting you unique abilities some others might not have. Your access to Stigma stones will increase with your level, and each time you reach that new milestone and get a new Stigma stone equipped (along with all your appropriate skills for your level) you will see the bigger picture here. Stigmas set you apart from other players by allowing you to customize your skills. A Templar is a good class to use here as an example because a Templar by default is the best tank, however, utilizing certain stones such as Stigmas that heal or do ranged stuns will also give them an arguable edge in PvP over PvE.

Stigma stones are rare drops from regular enemies found throughout the game. Named enemies tend to drop them in greater frequency. You will find that if you do not care to wait on drops, other players will be selling them. They usually fetch good profit as they are an in-demand item, although by using the account warehouse feature in your warehouse you can allow other characters you create to have access to them. This saves you the trouble later. Stigma Stones require a special NPC known as a Stigma Master found in each faction’s major cities. There is a cost to equipping them - Stigma Shards. By completing your Stigma quest at level 20 you receive some as a 1 time reward. After that you will need to obtain them by way of the Abyss; they drop commonly from enemies found there and add up over time. Keep in mind that the cost to equip the Stigma stone goes up with the level of the stone. Your level 20 Stigmas will be much cheaper to equip than higher level stones. Once you get a Stigma, you can change them out whenever you want without worrying about losing the Stigma stone itself since they return to you as you switch them out. It will be the shard cost to consider.