A player’s “opening hand” is the hand of cards the player has after all players have finished taking mulligans.

Unlike a normal token, a token card doesn’t cease to exist in a zone other than the battlefield. It’s both a token and a card. It can move between zones any number of times and continues to exist for the rest of the game.

If a token card is put into a hidden zone, you must use a supplementary token card with a Magic card back to represent it. Since these don’t exist yet, you may need to be creative.

For effects that look for or modify the creation of tokens, creating token cards isn’t the same as creating tokens

A Time Walk token card is a sorcery with mana cost {1}{U} and the ability “Take an extra turn after this one.”