As part of Adult Swim's April Fools' 2018 joke, he guest-voiced T.O.M. the animated host of Toonami, an American action cartoon block that frequently features Japanese anime. Starting at midnight, the show's bumps and typical anime programming switched to Japanese audio with English subtitles, with the disclaimers, text and even the [adult swim] logo all being shown in kana and kanji. In keeping with the joke, T.O.M. was voiced by Yamadera, introducing new shows in his native Japanese as well as doing a video game review of Nier: Automata. Ironically, and perhaps to further the prank, the normal English voice actor for T.O.M., Steven Blum also voices Spike Spiegel in the English dub of Cowboy Bebop, a role Yamadera shares with him in the original Japanese.