For Blackberry Margarita Base:

Combine tequila, lime juice, agave nectar, blackberry liqueur and water in a bowl. Place in heavy duty freezer resealable plastic bag. Place bag in freezer in upright position. Freeze at least 4 to 6 hours. May stay frozen for longer if desired.

For Blackberry Sangria Base:

Combine wine, brandy, simple syrup and water in a bowl. Place in heavy duty freezer resealable plastic bag. Place bag in freezer in upright position. Freeze for at least 4 to 6 hours. May stay frozen for longer if desired.

For Blackberry Fruit Base:
Lightly mash blackberries with simple syrup in a small bowl (just to blend the two, do not create a puree).

Remove frozen margarita and frozen sangria from freezer. Allow to thaw only until mixture is just pliable in the bag. Pour half margarita mixture in a goblet. Top with spoonful blackberry-simple syrup mixture. Top with half sangria mixture. Top with another spoonful blackberry-simple syrup mixture. Add remaining margarita mixture. Top with spoonful blackberry-simple syrup mixture. Add remaining sangria mixture. Top with remaining blackberry-simple syrup mixture. Garnish with lime twist and fresh blackberry skewered across top of drink.