Okay, I've stewed this over today and I have some thoughts.
I see this design going one of 2 ways:
1) You have a card that represents competition between Gimli and Legolas
2) You have a card which makes a competition between you and the Shadow player
1) I was thinking something like this might work:
Drinking Contest Event • Fellowship
To play, spot an Elf and a Dwarf.
Reveal the top 5 cards of your draw deck. If you reveal more
cards than
cards, heal that Elf twice. If you reveal more
cards than
cards, heal that Dwarf twice. Replace the revealed cards in any order.
2) A more sabaac-like mechanic (similar to some King cards like
Hosts Still Unfought):
Drinking Contest Condition • Support Area
To play, spot a Dwarf.
Maneuver: Place any number of Free Peoples cards from your hand beneath your draw deck. Then you must choose a Shadow player who can place any number of Shadow cards from his or her hand beneath his or her draw deck. For each card you placed beneath your draw deck more than that Shadow player, you may heal a companion. Discard this condition.