If a Spirit has a Growth Action that adds or moves its Incarna, can it just leave its Incarna in place (whether on the island or in the supply)?
If a Spirit has a Growth Action that adds or moves its Incarna, can it just leave its Incarna in place (whether on the island or in the supply)?
No, the Growth Action isn't optional: if the Incarna is in the supply, it must be added; if it's on the island already, it must be moved.
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).
Similarly, with its empowering growth option Ember-Eyed Behemoth can choose to move its Incarna to any land within range 1, including the land it's already in.
