Bloody Coin is a new currency added in Timeless Isle, which acquired through killing players. You can purchase Vengeful Porcupette and Reins of the Ashhide Mushan Beast with Bloody Coins, and gain Fire-Watcher title when getting 2000 Bloody Coins. 
Bloody Coin mainly gets from two items:
First one, Censer of Eternal Agony. Purchase by Timeless Coins in the Timeless Isle and the effect disappears if you die.
Use: Sacrifice 90% of maximum health to become an Emissary of Ordos. While transformed, you are hostile to all players, and killing players grants Bloody Coins. Can only be used on the Timeless Isle, and flags the user for PvP(1 Hour Cooldown).  Bloody Coin can not earn when killing the same player again. So you need to kill 600 players to get Vengeful Porcupette and Reins of the Ashhide Mushan Beast.
Second one, Fire-Watcher's Oath. Purchase by Timeless Coins in the Timeless Isle and the effect disappears if you die.
Use: Transform to Ordos Fire-Watcher. You can use the item in every place(10-minute Cooldown). Including Timeless Isle and out of it, and battleground. Killing a PvP-flagged player while under the effect of Fire-Watcher's Oath grants you a Bloody Coin.
Censer of Eternal Agony and Fire-Watcher's Oath come with transformation effect, the difference between the two is that you can kill any players in any factions when using Censer of Eternal Agony, while using Fire-Watcher's Oath can only kill players in the opposite faction. The two items are useful transformations if you don't like PVP.
After transformed the modeling of red, you may become the focus of others. Please be carefully in the wild!