Yes, it can only be used only every other turn. Phasing in and phasing out happen during the untap step before anything gets untapped. So when the Isle phases in, it gets to untap during that turn. When it phases out, if it is tapped, it doesn't get to untap during that turn.
If I’m using a card such as Teferi’s Isle, do I effectively only get to use it every other turn?
As I understand it..
Turn 1: Enters tapped
Turn 2: Phases out, unusable
Turn 3: Phases in and can now finally be used.
Repeat
Former Rules Advisor
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