LupitaNyong'o is playing Maz Kanata, a pirate whose castle is a meeting ground for "galactic travelers, smugglers, and other assorted riffraff." This is what she looks like with a bunch of dots on her face while being transformed into a Computer-generated imagery (CGI) charatcter.
Her appearance is still unknown, but it's possible that she is the alien character glimpsed briefly in The Force Awakens second trailer seen handing Luke Skywalker's first lightsaber, (Anakin Skywalker's second blue-bladed lightsaber), to an unknown human woman.
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