Mahjong again.

Ocean Floor Grinchlantis

1,5oz white rum
1oz blue curacao
0,5oz creme de cassis
0,5oz lime juice

Pour all ingredients to a shaker with ice and give it a good shake. Strain into a rocks glass with ice and garnish with a lime slice.
Visual appearance was the driving force of the idea here, but the end product was surprisingly good tastewise too