Not as Seen on TV Dejimon Teimâzu : Season 1 Episode 9

After the battle with Devidramon, Takato tries to make Growlmon de-digivolve into Guilmon, but all to no avail. When it begins to rain, Takato despairs of ever getting his old friend back. However, when the rain ends, Growlmon de-digivolves into Guilmon while watching the rainbow.