Forum:Triple Duel

Me, my brother and a friend like to have three-way duels. We each have a separate deck, hand, field, graveyard etc.

When attacking, we first choose which player to attack and then which monster. When using card effects, we decided that cards which state to destroy "all opponent's monsters/spell or traps" destroy all cards for both opponents but cards that state "destroy all cards your opponent controls" or similar target only one player.

Even though we know this isn't grammaticality correct, when applying damage-causing effects we try so that cards that say "opponent's" target both opponents and cards which say "opponent" target only one.

Anyone have any suggestions on how to improve this system? I don't know of any 'official' way to do this.