That game doesn’t need any more uncertainty.
[color=yellow]True, but it would diminish the power of the card. It is usually held back until the last trick and other players do not know if the card is out or not... uncertainty. If a player is holding the card it is more likely to be played earlier. Ergo, less uncertainty not more.[/color]

Would it be better to have Excalibur card only cancel trick if played in ODD position?