Carl's Dad Caverns

 is a limited-time decoration released on May 17, 2016, as part of the Wild West 2016 Event. It's the ninth and final prize to be won in the Event's Act 3.

About
 are caverns in Springfield, discovered by Carl's dad in 1956...

Regular
Carl
 * Search Carl's Dad Caverns - 60m

Event Quest Based
Carl Homer Lisa
 * Treat His Glaucoma - 4h
 * Dig Into Carl's Past - 2h
 * Leave the Cave With Lisa - 4h
 * Search Carl's Dad Caverns With Homer - 60m

Character Groups

Rigelians
 * Treat Their Glaucoma - 4h

Trivia

 * Only one can be obtained.