The footnotes on the Festival page state that your removed meeple can be: “All of your own figures are meant here, including normal and large meeples, wagon, mayor, builder, pig, barn, shepherd, phantom, abbot meeple, ringmaster, and guard meeple."
And then: “If the Festival is used to remove a meeple, the Phantom can still be placed on that turn.”
So, the question is, can you remove the Phantom from the board, then use it as the second meeple placement?
My guess is that you can’t place it at the end of your turn if you did not have it in your stack at the start of your turn.
If it is not legal, it could make an interested house rule!
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