Musical Battle (3.5e Variant Rule)
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 Musical Battle
When two or more Bards are in the same combat on opposing sides, the bards make an Opposed Perform Check using whichever instrument they're currently playing. For all bards except those on the winning side, all effects of their Bardic Music abilities and other abilities which require them to play music are negated, as only the bard who plays best can truly inspire his team.