Mash the avocados with a fork on a plate or use a mini food processor.
Add the yogurt, finely chopped red onion, and lime juice.
Season with sea salt, and pepper to your taste.
Spoon the guacamole into a small bowl or platter.
Mix the ingredients for the garlic dip (Greek yogurt, onion powder, minced garlic) and season well.
Dollop the garlic dip onto the guacamole and shape the dollops into round 'eyeballs'.
You need 5, 7, or 9 eyeballs (go for an odd number).
Cut 3 thin slices of cucumber and trim irises for each eye with a small knife.
Place the cucumber irises onto the garlic dip eyeballs, and top with capers.
To make the skulls, cut 7 slices of cucumber.
Shape two right-angled indents to each side of the slices, creating a jaw.
Trim two small indents in the jaw to resemble teeth.
Cut out eyes with a metal straw.
To make the nose, insert the straw at an angle, and remove the top half of the cut out with a small knife.
Scatter the cucumber skulls onto the dip.
Place the guacamole on top of a platter and serve with chips, cucumber slices, crostini, crackers, etc.