Q: If I used the power of the Guardian of Forever to get an extra turn, then played Brain Transference, does my opponent now in my seat get the extra turn, or do I?

A: To review: By taking the Guardian of Forever (GoF) out of play in front of you, and putting it in the middle of the draw deck, you are granted an extra turn after your current one is finished. Brain Transference says you put your hand down, leave your Keepers on the table, and switch seats with one of your opponents: they get your hand, your Keepers, everything, and your turn ends immediately. The person who would normally go after your previous seat now takes their turn (or, in a two player game, the person now in your former seat).

This is a very tricky question which we debated for quite a while. It’s so complicated that we’re not even going to go into all of the questions that might hurtling around your head right now.

The official ruling from Andy is that the extra turn granted by the use of the GoF stays with the player who originally invoked it (we’ll call them Player A), not the opponent now in their seat. When does Player A get their extra turn? Right away after the Brain Transference abruptly ended their last turn, so, before anyone else goes.

It would go like this:
Player A has the GoF in play. As a free action, they take it out of play and insert it into the middle of the draw deck. They continue with their turn, and, for whatever reason, end up playing Brain Transference.

Player A picks Player B to “swap brains with” and both players set their hands down and switch seats, and Player A’s turn ends.

No matter where Player A is now sitting, they take the next turn: the extra one they gained by using the GoF.

Then the game continues as it would after the Brain Transference. If it’s a two-player game, then Player B, who is now in A’s former seat takes their turn. If there are more than two players, then whoever is sitting in the seat “after” Player A’s former location (we’ll call them Player C) takes their turn. (Playing clockwise, that would be the person to the left of Player A’s former seat.)