LotR TCG Wiki: mulligan

Mulligan is a rule specifically made for tournaments which permits players to shuffle their starting hand back into their deck at a penalty (redrawing only 6 cards instead of the usual 8) if they decide that hand was too poor. This was done as in other card games to try and alleviate poor luck somewhat and reduce friction in a tournament setting.

This ruling has since been widely adopted for casual play within the community.

From the Official Tournament Guidelines:

Redrawing your hand

After all players have drawn their starting hands (before the first turn begins), each player (in player order) may shuffle his or her hand into his or her draw deck and draw 6 cards.
The cards in the original hand are not revealed to anyone. This redraw may be for any reason. Each player may redraw only once per game. A player who passes on the opportunity to redraw may not change his mind.

See also this thread on the old CobraCards forums.

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