Sugar skull

A Sugar Skull is a collectable featured in the "Day of the Dead" challenge in The Sims 4. There are 9 unique sugar skulls that can be collected and a 10th gold one that will be unlocked if a Sim uses the "Honor the Dead" interaction on a Sugar Skull Display Case with all 9 unique sugar skulls.

Collecting a Sugar Skull
Sugar Skulls can be obtained by Day of the Dead celebrators, who will spawn on the lot if a Sim has offered a Sugar Skull to a gravestone at night. Sims can "Ask for Sugar Skull" and be given one, sometimes the celebrator needs to chat with the Sim in order to give one out.