Tales of the New Teen Titans #3 (1982)

Changeling
Origin of Changeling. While roasting Wieners around the campfire (and burning most of them inadvertently while talking), Changeling recounts his origin and early life to his Teen Titans teammates. He explains how his medical researcher father accidentally gave him his shape-changing powers and green complexion while curing him of a jungle disease, how his parents later died in a flood, and how, after many adventures, he was eventually taken from the cruel guardianship of Nicholas Galtry and adopted by Steve (Mento) and Rita (ElastiGirl) Dayton and allowed to join the Doom Patrol (all told in greater detail in Doom Patrol #112-115 and #99-110). He then goes on to relate his exploits after the demise of the Doom Patrol (in Doom Patrol #121). After a brief adventure with the earlier Teen Titans team (told in Teen Titans #50-52), he had returned to his acting job with the Space Trek: 2022 TV series, during which an old Doom Patrol foe, the Arsenal, made an unsuccessful attempt on his life. Out of work after the series’ cancellation, Gar was reunited with his high-school girlfriend, Jillian Jackson, only to have the Arsenal return and kidnap her. Trailing the armored villain to his castle hideout, Beast Boy (whose dual identity, it should be noted, was known to the world by this time) discovered that the Arsenal was actually his former guardian, Galtry, who had hired the original Arsenal to eliminate the Doom Patrol (in Doom Patrol #113) and who had now usurped that costumed criminal’s identity himself. His goal: to hold Jillian for ransom and regain the money he had lost when Gar Logan’s guardianship had been taken from him. Beast Boy contacted Vernon Questor, who was in charge of Steve Dayton’s finances while Mento searched for the killers of the Doom Patrol, but was unable to attain the needed ransom money. Galtry then left him trapped in an airtight room while he attempted to get the ransom paid by Jillian’s father instead. Escaping, Beast Boy battled Galtry/Arsenal, shattered the villain’s armored costume, and defeated him.
Release Date: 1982