While the most powerful Fallen can perform Conjunctual Synthesis through only two themes, called Eminences, even this limited contact with the River of Dream can bring about powerful changes in the Material Orb. A few of the more savvy and occult of the Fallen have discovered a new key to even greater power by threading their two Eminences together to bring even more powerful currents of the River of Dream to flood into the world of flesh.
Put simply, when a given effect takes both a character's Eminences into account, that character can wield even greater power in their Conjunctual Synthesis, and add to their roll a modifier equal to their Synthesis score.
The Weaver should keep careful rein on the use of Dual-Eminence Conjunctual Synthesis, as it is a great temptation to players to 'tack on' an extra Eminence to get the modifier. Whenever this House Rule is invoked, each Eminence should be integral to the attempted Synthesis so much that the effect could not be performed without both Eminences being involved.
The Weaver can also limit this House Rule by ruling that knowledge of this technique is limited to only a few of the most powerful or ingenious Dreamers.
The only problem with this technique is when the Dreamer fumbles: with both eminences drawing so much more power of Dream into the material orb, the threat of lost eqilibrium becomes worse. When rollling for the effects of lost equilibrium, the player uses her Synthesis score as a negative modifier to their PSY roll, making the chances of being swept away on the tides of Dream all the greater.
In the example at the top of this page, Sade has the Eminences Conflict and Recognition. He uses both to examine the Conflict and Recognize who is to blame. He rolls his three dice (a 2, a 6 and a 6) for a result of 7, adds his PER of +1 and then his Synthesis of 3, for a total of 11!
The Seeress Dannae, with Eminences of Fate and Mystery, uses her Destiny Deck to scry the future of the stranger who has come into her wagon. She simultaneously looks forward into the man's Fate as well as looking inward to puzzle out the Mystery of his identity. Hopefully she will recognize that he is a scout for Boarhead, here to judge the defenses of Hom... She rolls her two dice (a 3 and a 5), adds her PER of +2, and then adds her Synthesis score of 2, totalling up to 9.
With the cries of Z'bri echoing through the forest, Janz uses both Illusion and Freedom to contort the trees so that he cannot be seen, allowing him to escape. He rolls his two dice but fumbles -- two ones. Making his PSY roll for Lost Equillibrium, he rolls a 3 and a 4, has no PSY modifier, and then subtracts his Synthesis of two -- garnering himself Major Disconnection. Janz collapses in the forest, screaming at the snatching, grabbing trees.
Staring down the Watch as it forms a loose circle around her, Marya dips into the River and brings her two Eminences, Fury and Vengeance, to turn herself into a battle valkyrie, ignoring wound penalties and assisting in all her attack rolls. She rolls her sole Synthesis die (6), adds her FIT +2, and her Synthesis of one to total up to 9.
Special Warrior Unbound Note: If anyone knows the secrets of dual-eminence synthesis, it is the Guides: given the fact that they have access to more than just one eminence, this rule may go a long way to explaining their power. While it is doubtful that three or more eminences could be used in conjunction with eachother often (and I'm not even touching rules for that sort of mojo), at the very least the Guides have a greater range of combinations between their various Eminences.