Basically, if you occupy 5 dimensions or affect a construct that is stated to be 5-dimensional, yet the dimensions in question are not stated to be a higher level of infinity or qualitatively superior, would you still receive Low Complex Multiversal Range?
Frankly, I'd rather not have anyone attempt to answer this question authoritatively, now that I look back at our
Range page and realize how inconsistent and barebones it is. Regardless of what anyone thinks, the written standards on the matter are not clear at all, as shown by this, for example:
Universal+: Attacks and abilities that are able to reach anywhere within a single 4-dimensional space-time continuum.
No specification for the size that this spacetime continuum has to be at, something which, if applied straightforwardly, would mean being able to access all points in space across a time interval of, say, two seconds, would be enough to get you Universal+ range (And that's not even getting into the fact that it neglects cases where all four dimensions are spatial). The same applies to all other higher ratings: They largely just say "Attacks and abilities able to reach throughout n-dimensional space," without specifying the size of those spaces, and it gets even worse at Hyperversal and up, which just list "Attacks and abilities that are able to reach 12/infinite/uncountably infinite-dimensional space and above."
As for my take on what the standards should be: I'll admit I am a bit split, in that regard. Firstly, it should be noted that, even if a higher-dimensional being is finitely powerful, it will naturally always have infinitely more volume than a lower-dimensional one, being itself comprised of infinitely-many cross-sections of one dimension lower, and so by that token, one could argue that being able to affect (Or occupying) every point of a higher-dimensional volume would be equivalent to infinite range.
However, on the other hand, it should be intuitively obvious that a higher-dimensional being might not necessarily be able to affect all points of a lower-dimensional space, even if the latter has 0 volume compared to them, because the numerical values that they themselves have may differ heavily. For example, imagine a board that extends infinitely in the x-axis and the y-axis, but has no extension in the z-axis, and is thus a 2-dimensional plane; even if you, as a 3-dimensional being, have infinite volume compared to it, I don't think you'd claim to be able to reach through the entire board at once (Unless you're on some serious drugs, of course).
So, given that, you could end up just giving Interdimensional range to such beings (Higher-dimensional "melee fighters," as it were), like DontTalk and Agnaa discussed above.
What the other ways are concerned: There are definitely ways to get there without statements of qualitative superiority.
I'm not sure about the 3. requirement, though...
For 1. we actually don't demand infinity, but only proof of significant size (i.e. it should not be rolled up quantum mechanics stuff).
That much was confirmed in the ToAru revisions after the system change, where it was checked whether they should stay tier 1.
Honestly I think confusion in that regard is largely on us. To once again quote the Tiering System FAQ:
However, vaguer cases where a universe is merely stated to be higher-dimensional while existing in a scaling vacuum with no previously established relationship of superiority towards lower-dimensional ones (or no evidence to infer such a relationship from) should be analysed more carefully. In such cases where information as to their exact nature and scale is scarce, it is preferable that the higher dimensions in question be fully-sized in order to qualify.
As you may notice, we don't really make it at all clear what a dimension being "fully-sized" means, and this ambiguity may prove very problematic for us. You can interpret it as being anything from "infinite" (Like R itself is) to "as large as our observable universe."
