Many Mythic Paths in Mythic Paths of the Lost Spheres support multiclass characters but as of yet there aren’t many multi-path mechanics out there despite the Dual-Path feat. But the possibilities are endless for path interaction and one such option squeeks out for the Halloween Witching Hour:
For the Worldsinger AND Hollow One mythic path from Mythic Paths of the Lost Spheres:
Curse of the Moonsong (Mythic)
Your song carries the power and burden of your lycanthropic curse to allies hearing your song.
Prerequisites: Dual-Path feat, Carrying Chord and Caress of the Afflicted path abilities, afflicted with a curse of lycanthropy.
Benefit: While performing to grant a morale bonus to your allies you may cause the magic of your song to touch them with your curse’s power. You may expend a use of mythic power to grant allies gaining a morale bonus from you all the benefits of your lycanthropy. This effect lasts up to 1 minute per tier or until your morale effect ends, whichever is sooner. At the end of this effect, the allies benefiting from your morale effects must save against your original curse’s effect DC or contract the same lycanthropic curse themselves.
You can get Mythic Paths of the Lost Spheres on: RPGNow or Paizo or d20.pfsrd.com!
"Find the Hero Within" - Lost Spheres Publishing 