If Retreat is used on Blue Viktor, will he spawn the token before he bounces back?

Ruling: No, Viktor will not spawn the token. A card has to fully resolve to be considered "played", so Viktor's ability won't trigger because he won't be on the board long enough to see Retreat finish being played.

Nuances:

• If Viktor would be killed by an opponent's card and you react with something like Stupefy, Viktor's ability would trigger when Stupefy resolves and go on the chain above whatever effect is killing Viktor
• A judge at the Vegas Tournament ruled incorrectly in favor of token generation, but this was confirmed to be wrong by multiple community members