(I'm glad we use the French name for this holiday. "Fat Tuesday" doesn't sound nearly so exotic.)
One of my enthusiastic students, Janet, regularly visits a seniors home and does a variety of zentangly projects with several of the residents. They had a Mardi Gras party and she helped her group make some masks. Here are her samples.
Here are the masks made by the residents, complete with Mardi Gras colors green and purple embellishments.