Othinus can destroy the universe and all phases simultaneously (except the hidden world of nonexistence) i.e. she destroyed everything in the ToAru verse with one exception:
That would include the hundreds of billions of phases (i.e. dimensions) Othinus created to torture Touma:
Those phases are each universal in size (there are even more phases she destroys but those are possible not universal in size).
Now why they are universal in size is a bit hard to show by a brief quote.
It's simply that Othinus first completely erases the world (
we see complete blackness with no stars at all in an image and are told there is nothing 360° around) and then starts creating one world after another, which are all altered copies from the original one.
Like, she creates a world which is the same but people decided Touma is the enemy. Or she creates the "Happy World" in which everyone got saved, nobody had to die before their time and every problem in the world was resolved.
That's the entire content of the Volume NT 9 so a little hard to put into a single quote. Maybe a few here:
Pretty sure goldenboy had a bunch more quotes on the subject somewhere in his collections.