McDonald's Mexican cousin is turning 20 this month, and to mark the occasion it's throwing a pre-legal birthday party that actually won't suck. Beginning on July 13th, Chipotle will host a 20-day treasure hunt that promises two decades of free burritos to 20 overfed winners. Here's how the so-called "Adventurrito" works. On each of the first 19 days of the contest, Chipotle will release a puzzle. Players that correctly solve all of these puzzles will get a shot at the final day Thunderdome. The first 20 contestants in this elite group to solve the last puzzle will score 52 free burrito cards every year for the next 20 years of their lives. Which we'd ballpark equals about five metric tons of cilantro lime rice. If you want in on this amazing treasure hunt (whatever, Jim Hawkins), you better sign up on the official site right now.