Den-O's Final Stage involves the Imagins forgetting about Ryotaro, due to villain shenanigans. It also features heavy use of Plat Form and Ryotaro's unwavering belief in the imagins.
Keiwa: Mind if I defeat you? Can’t hear your answer.
Geats cast and some Riders react to Keiwa being possessed by the Imagins
Neon: *pouting* *shakes Keiwa violently to try getting the Imagin out* Give him back you stupid Imagin! Get out of my tanuki!!
Keiwa: *momentarily breaking free of the possession* Neon-chan, stop, I'm getting dizzy already- Wait what? Your tanuki?
Sara: *holding the other Imagin hostage* What do you have to say for yourselves?! *holds Magnum Shooter to Momo's head* Why are you messing with my baby brother?!
Ace: *calling Ryoutaro* Ah, yes, senpai... I've found your Imagin friend. If you'd be so kind as to retrieve them, because they may just end up dead at the hands of Tycoon's sister and girlfriend.
my brain, for some reason, tried to guess that real-action (from kamen rider den-o) was from phineas and ferb and now i'm imagining ryoutarou in phineas and ferb