Everyone knows by now, you must do a quest at level 20, in order to start using Stigma Stones. Once completed, the quest will award you your first Stigma Stone as well as 80 Stigma Shards. The shards are used as payment to the Stigma Master when you socket your stones.
Once you complete the level 20 Campaign quest for your faction that leads to your first Stigma Stone you will also open up two slots to equip them in. After that a new slot will be available every 10 levels. (I.E.: 2 slots at level 20, 3 slots at 30, 4 slots at 40, etc.)
Stigma Shard cost is four times the level of the stone. (I.E.: for a level 20 stone you will need 80 shards. For a level 30 stone you will need 120 shards.)
The following quest chains will be need at level 20, and completed before you will be able to equip and use the stones.
Memory of the Past
No Escaping Destiny
The Stigma Masters can be found accordingly.
Elysean Stigma Master
Orphe – Sanctum
Asmodian Stigma Master
Aud – Pandaemonium
At level 20, the following stones will become available. I believe NCSoft has the verbage incorrect here, as the Glad stones and Templar stones seem 180° off to me. For example, I would prefer a Templar, Ranger, or Spiritmaster stone for a Gladiator.
Here are the “class”, “Ability”, and “Ability Action” for each stone type.
Increases your Physical attack power by 30% for 30Sec.
Recovers your HP by 20% and increases your Max HP by 20%, shield defense by 150, and Weapon Defense by 100 for 2Min.
Chain Engrave Signet
Inflicts 34~38 physical damage on the target and engraves a signet pattern on the target up to the level of 3.
Inflicts 122~126 physical damage on a target within a 15m radius of you and other enemies within a 5m radius of the target.
For 15 sec, you can use a skill with only 50% of MP that is needed to use the skill.
Inflicts 279 magical fire damage on a target within a 25m radius of you, and absorbs 50% of the damage as HP.
Grace of Empyrean Lord
For 12 sec, you can use a skill without consuming the MP that is needed to use the skill.
For 30Min, your Physical attack power increases by 15%. But in the meantime your healing skill casting time also doubles.