Mothra really had Godzilla's number in the Show series.... (Spoilers)
Godzilla versus Mothra
- The first Mothra knocks Godzilla to the ground before flying away to die protecting the egg
- The two new Mothras web Godzilla up and drop him into the ocean
Ghidorah, the Three-Headed Monster
- Mothra breaks up the fight between Godzilla and Rodan by webbing them both
Godzilla versus the Sea Monster
- Godzilla is knocked to the ground by Mothra who then flies away to rescue the islanders
I don't know if these are new generations of Mothra or the same one, but Godzilla lost every time or at least never got in the last offensive move. Watching Godzilla and Mothra: Battle for the Earth, it was very satisfying to watch the caterpillar Mothra knocked out of the water by Godzilla. It's just a shame that it's a different Mothra or, at the very least, a different line of continuity.