Board Thread:Questions and Answers/@comment-33935463-20180426192324/@comment-38952966-20200802230820

RetroScoob wrote: You know I was thinking since Reality Overwrite is basically a strong move like Return to Zero and can, since the name states, overwrite reality. Doesn’t that mean he could revert the effects of RTZ off of himself (HA DIO) through TWOH since you could say he’s in the reality that the world is reverting back to the origin (which we do not really know at most) and still fight GER in his regular position?

According to the rules implied by EoH, in order for DIO to make himself immune to something with The World Over Canon, he needs to be exposed to it or aware of how it works first. Since you can't experience RtZ without being affected by it, GER SHOULD be able to RtZ faster than DIO can overwrite.

It's also shown that, in the case of something extremely powerful (like GER), DIO has to touch what's directly affecting him, and not just make himself immune. For example, he had to touch Tusk ACT 4 and GER to counter their abilities, rather than just making himself immediately immune. However this is likely because of the first reason, i.e. he has to be aware of how the ability works in order to counter it.