Is it possible to spare Magus but also cure Frog in Chrono Trigger?
Solution 1:
This ending it's called in the wikia as Revenge for Cyrus
If you face Magus in Noth Cape with Frog on face to face battle, sparing him or killing him will result in this ending after defeating lavos.
Furthermore, killing or sparing him changes a little the final sequence but in both cases Frog becomes Glenn (human) again.