Depending on the Power and Incarna in question, this may be weaker than when used by the original Spirit. For example, while Frightful Keening can still push the Incarna of Wandering Voice Keens Delirium, and still generates Fear if pushing into a land with Invaders, only Wandering Voice Keens Delirium can use this Power to add Strife via Keening Spurs Grievances. Tags: Transferring Power Cards, Incarna, Entwined Power, Blazing Intimidation (Ember-Eyed Behemoth), 7 more...
That being said, you can count an Incarna on the island as Presence for the purpose of checking where it moves. So, e.g., Wandering Voice Keens Delirium can count its Incarna as the Presence it's moving the Incarna to, thereby moving the Incarna to the land it's already in (which would then add Strife with Spread Tumult and Delusion).
While this tends to be pretty obvious when the cost is paying Energy, it's less clear if the cost is performing some other effect, like discarding a card or removing Presence.
While you must be able to pay the cost in order to get the bonus, ongoing effects can alter the final result of the cost being paid. For example, you can successfully pay the cost of "Destroy 2 Presence" even if Flowing and Silent Forms Dart By will end up saving that Presence from destruction if you do so. On the other hand, you can't attempt to pay the cost with Presence under Absolute Stasis, since that Presence only exists for Victory/Defeat – it doesn't exist as far as the Event is concerned. Tags: Action Modifiers, Flowing and Silent Forms Dart By, Absolute Stasis (Fractured Days Split the Sky), Turmoil's Touch (Wandering Voice Keens Delirium), 11 more...
This holds true even if you're restricted on which Elements you can choose (e.g., Wounded Waters Bleeding having a "Water / Animal" space instead of a full "Any"). [Nature Incarnate rulebook p. 9]
