A major moment in Godzilla history was reversed in Godzilla: King of the Monsters. In the final battle with King Ghidorah, Mothra sacrificed her life energy so that Godzilla could beat the three-headed dragon. Something similar happened in 1993's Godzilla vs. Mechagodzilla II, except that in the Toho movie, this role went to Rodan.
The battle between the four Titans in Godzilla: King of the Monsters culminated in a two-on-two showdown with Godzilla against King Ghidorah, and Mothra taking on Rodan, who had accepted Ghidorah as the alpha. After being mortally wounded by Rodan, Mothra swept in to help a struggling Godzilla. Energy from her body flowed into Godzilla, allowing him to morph into his fiery form. As Burning Godzilla, he easily overpowered King Ghidorah, defeating the alien with ease. Unfortunately, the cost of Godzilla's powerful transformation was Mothra's life.
Related: King Of The Monsters Changes What Godzilla Means (& That's Why It's Great)
The final battle in Godzilla vs. Mechagodzilla II took a much different turn with the key monsters. Rodan, who was fighting to save his "brother", Baby Godzilla, was badly wounded while fighting Mechagodzilla. Godzilla arrived to fight in his place. After Mechagodzilla destroyed Godzilla's second brain, his death appeared imminent. Rodan intervened by landing on Godzilla's body, transferring his remaining life force. Afterward, Rodan's body dissipated into the air. Rodan's energy was able to reconstruct Godzilla's second brain and provide him with a huge boost in power, as well as an improved version of his spiral heat ray, which was red instead of blue. Much like Ghidorah at the end of Godzilla: King of the Monsters, Mechagodzilla stood no change against the refueled Godzilla.
Rodan's sacrifice holds great meaning in the 1990s series of Godzilla movies, considering how it preludes 1995's Godzilla vs. Destoroyah, the movie where Godzilla achieves his burning form. In fact, it may have inspired Godzilla's actions; when Godzilla was dying from being overloaded with radiation, he breathed the last of his energy into his son to ensure he could become the new Godzilla. That made the sacrifices of Godzilla and Rodan all the more poetic as they both ended up giving lives for the same reason: Baby Godzilla.
Godzilla vs. Mechagodzilla II gave Rodan his best story. Yet in Godzilla: King of the Monsters, that goes to Mothra. Far from an insult to the fire pterodactyl, though, this is merely reflecting their differing presentation in the new movie to the previous canon. Indeed, what makes this reversal even more interesting is that the character who takes Rodan's arc is also killed by Rodan. Director Michael Dougherty clearly worked hard to ensure fans of either monster didn't walk away unsatisfied.
With Rodan still alive at the end of Godzilla: King of the Monsters and there many ways for Mothra to return, this needn't be the end of the pair's new interactions in the MonsterVerse.
