I am thinking that this happened when Writer's Block "fought" the Bunny Dragon in the movie presumably about rescuing the President,
It turns out that BD was being controlled by the Mysterious Evil Wizzard. And WB is able to release BD from MEW's control. When BD is free from MEW's control, he takes WB to the dungeon where MEW was holding Cliche Princess. BD gives CP and WB a ride to MEW's hidden lair where he is holding the President. It turns out that MEW is actually the Vice President who is able to stand his ground against BD and WB only to be taken by surprise by CP.