Originally posted by MrMind
it was a statement by Tyrant himself saying when he was full power he can perish galaxies at his whim
http://i.imgur.com/FDAlYtZ.jpg
which is backed up by narration statement during the Tyrant and Galactus fight
https://i.imgur.com/tz7OS50.jpgfull power tyrant was a threat to the universe, he can more likely survive universal destruction then not, there's also option of defeating Monarch without rupturing his armor
http://i.imgur.com/BGiZm5i.jpg
1) Could be Hyperbole. If it isn't then it's still open to interpretation of what "perish galaxies" mean.
2) "Emnity raging between them must have destroyed galaxies" has several problems.
A) Emnity is a state of being or a feeling. It's not an action.
B) "Must have" leaves some doubt to whether it happened. Otherwise those two words could have been left out.
C) There are more than millions of different levels of destruction and EACH level could have taken an indefinite amount of time. Which level did they achieve (bare minimum or absolute disintegration) and how long did it take them (a few minutes or a few days or years)? There are more than trillions of times more power needed in one scenario than in another.
In summary, we can't be 100% sure they destroyed any entire galaxy (part of a galaxy sure). If they did then we can't be sure of the level of destruction. Lastly, we do not know how long it took them. Could have taken many years for all we know.