At 18th level, you can use a bonus action to create two echos with your Manifest Echo feature, and these echoes can co-exist. If you try to create a third echo, the previous two echoes are destroyed. Anything you can do from one echo's position can be done from the other's instead.
In addition, when you roll initiative and have no uses of your Unleash Incarnation feature left, you regain one use of that feature.
By 15th level, you've learned to absorb the fleeting magic of your echo. When an echo of yours is destroyed by taking damage, you can gain a number of temporary hit points equal to 2d6 + your Constitution modifier, provided you don't already have temporary hit points.
You can use this feature a number of times equal to your Constitution modifier (a minimum of once). You regain all expended uses when you finish a long rest.
Starting at 10th level, you can make your echo throw itself in front of an attack directed at another creature that you can see. Before the attack roll is made, you can use your reaction to teleport the echo to an unoccupied space within 5 feet of the targeted creature. The attack roll that triggered the reaction is instead made against your echo.
Once you use this feature, you can't use it again until you finish a short or long rest.
Starting at 7th level, you can temporarily transfer your consciousness to your echo. As an action, you can see through your echo's eyes and hear through its ears. During this time, you are deafened and blinded. You can sustain this effect for up to 10 minutes, and you can end it at any time (requires no action). While your echo is being used in this way, it can be up to 1,000 feet away from you without being destroyed.
At 3rd level, you can heighten your echo's fury. Whenever you take the Attack action, you can make one additional melee attack from the echo's position.
You can use this feature a number of times equal to your Constitution modifier (a minimum of once). You regain all expended uses when you finish a long rest.