Despite surviving Godzilla: King of the Monsters, Rodan didn’t come back for the next MonsterVerse showdown in Godzilla vs. Kong. Unlike Mothra and Ghidorah, Rodan made it through the final battle in Boston, where he bowed down to Godzilla and accepted him as the new alpha. The King of the Skies becoming one of Godzilla’s new Titan minions effectively set up a role for the character in a new Godzilla movie.
However, a role for Rodan in Godzilla vs. Kong was not in the cards. In fact, not a single mention of him or his whereabouts was included in the movie. As for where he was, the novelization of the movie revealed that Rodan is currently inactive in the MonsterVerse. It was said that he’s still nesting in the volcano in Fiji that he found after King of the Monsters ended. Apparently, Godzilla saw no need to call him out of hibernation for the fights that unfolded in the MonsterVerse’s fourth installment.
In an interview, Godzilla vs. Kong director Adam Wingard shed light on the reasons for why Rodan didn’t return. Wingard has explained that using the Titan would have been a costly move. He said it reached a point when they had to be “very choosy” about how they spent their money due to budget concerns [via Toho Kingdom]. This, combined with Rodan not having a clear place in the story led to the monster being excluded from Godzilla vs. Kong.
While fans may remain hopeful that Rodan team up with Godzilla in a different movie, Wingard’s comments highlight the problems with bringing him back at all. It would seem that the deal that allowed Legendary to use the character for King of the Monsters didn’t extend beyond one film. If it did, he’d certainly be a more attractive choice over most other Toho kaiju. So if Legendary wants to use him a second time, another rights purchase will have to be made. If another large sum is necessary just to get Rodan back into the action, the studio may simply take a pass on the kaiju and let him continue sleeping in his volcano. If Legendary does end up relying on another Toho property if and when it makes Godzilla 3, it may reserve that money for whoever their villain choice is, whether it be Biollante, Destoroyah, or someone else.
Regardless, Rodan not returning in Godzilla vs. Kong did make sense narrative-wise, especially since he would have made the battle a bit lopsided. Godzilla may have felt that he didn’t need any help. The addition of Rodan and King of the Monsters’ original Titans would have complicated matters in a big way since Godzilla and Kong’s battle needed to be a one-on-one match. That being said, it would most certainly be a disappointment if Rodan didn’t return for Godzilla 3. Even though he’s commonly regarded as Godzilla’s best ally in Toho’s movies, he was denied a chance to fight at Godzilla’s side in King of the Monsters. How his story ended made a team-up that paid tribute to their past adventures possible, so it would feel like a missed opportunity if that never happened.