Wirakocha

Wirakocha is an Incan trickster god.

History
When the Simpson family traveled to Machu Picchu in search of Bart, Homer found a bush shaped like Bart's head. He ran up to the bush, thinking that it was the real Bart. When he realized it wasn't Bart he remarked that it must've been "the work of Wirakocha, the trickster god."

Behind the Laughter
Homer is likely referring to the Incan god, whose name has the alternate spelling of "Wiracocha".