Digimon Tamers Season 4 Episode 10 Opposites Attract

While searching for Gatomon's tail ring, Yolei, Kari, Ken, and their Digimon stumble into the Dark Ocean. When they are attacked by Blossomon, another of Arukenimon's creations, Gatomon and Aquilamon DNA digivolve into Silphymon (only after Yolei slaps Kari in the face, something Kari did earlier in the episode).