If a player draws extra cards (e.g., 2 cards instead of 1 at start of turn), does the remedy really require revealing their entire hand to the opponent who then chooses which card(s) to shuffle back?

Ruling: Yes, if the extra card(s) are added to the player's hand (private set) and the error is caught within the round cycle, the opponent looks at the entire hand and chooses which card(s) to shuffle back into the deck. This is intentionally harsh to discourage cheating.

Sequence:

• If extra cards are drawn but NOT added to hand (kept separate/face-down), simply shuffle the identifiable extra card(s) back
• If extra cards ARE added to hand, opponent gets to look at entire hand and select card(s) to remove

Nuances:

• The harsh penalty (opponent choosing) exists because drawing extra cards is easy to cheat with and was historically a game loss in other TCGs
• Competitive players often draw cards face-down to the side first before adding to hand, specifically to avoid the harsher penalty if they accidentally draw extra
• If you don't look at the extra card and catch it immediately, you may not be in violation at all
• This remedy matches what Magic: The Gathering used successfully for over ten years