When he was a 20-week-old embryo before he even had a real name Choi Hee-woo became one of the world's youngest-ever plaintiffs by joining a groundbreaking climate lawsuit against South Korea. His case, known as "Woodpecker et al. vs. South Korea" after Choi's in utero nickname, seeks to prove Seoul's modest climate goals reducing carbon emissions by 40 percent of 2018 levels by 2030.