Suggested Farm #2: From Tihark Orchard, head southwest through Forum Highlands and go into the second gorge on the left. At the bottom of the root bridge, 3 groups will converge; these groups will be either 3 Roaring Ethers or 2 Ethers and 1 Sapphire Djinn. The boss group with Churahm, Spirit Warrior will have another 3 Ethers, and the 3 groups of djinn will sometimes contain an Ether. Once you're done with these groups, go to the south and then, after the harpy group, to the west, and you should meet three groups of roaring ethers with the boss Korshek the Immolated and random djinn.
Pre cast WoP and SoD, DP+SF before engaging, make sure to make a nice ball, cast Glyph, MoR, FS or BoC, wait a few seconds and cast last AoE. If lucky all should be dead by now, but most of the times 1 Roaring Ether survives and will res. The ressed Ether won't res more most of the times. I used this build to kill mobs starting from Dzagonur Bastion.
Suggested Solo #2: A variant of A/N Perma Solo does well in the Mirror of Lyss. The blessing doesn't help the farm. Target the djinn first. Kill the same Roaring Ether until all the res signets are used.