1Mix blood orange juice, lime juice, liqueur, tequila and agave nectar; strain into large pitcher. Refrigerate until chilled, at least 30 minutes.
2Moisten outer rim of 8 glasses with orange or lime, and dip rims into salt to lightly coat.
3Add ice to pitcher, and stir well. Pour into glasses. Garnish with blood orange slices, and serve over crushed ice.