Shahrazad and Sindbad (Playtest Card)

'Whenever Shahrazad and Sindbad deals combat damage to an opponent, if there haven't been any subgames this match, players play a Magic subgame using their libraries as their decks. Each player who doesn't win the subgame loses half their life, rounded up.
{T}: Draw a card and reveal it. If it isn't a land card, discard it.