What tier is this?

[MasqueTLDF]

I'm wondering where this feat scales.
1. Tsubaki is stated to be able to destroy "the world" (This is a fantasy setting so I'm not sure of the cosmology size.)
2. There is normally a sun that exists. (Update: Starry Sky confirmed!)
3. Her ability "Reset" which was what was stated to destroy the world leaves behind only a black void of nothingness.
4. Is described as "Rewriting Causality" with this ability.
5. I think it's below Low 2-C since the MC is still able to time travel, though he's stated to "exist outside of causality" so I'm not sure if that exactly applies.
I'm thinking it could range from 5-B to 4-C, though it could possibly be Tier 3. And this'd only be Environmental Destruction right?

 

[Mudducky04]

1. Understandable
2. Since the setting has a sun, this could suggest that the cosmology includes a solar system, and this could push the scale higher if "destroying the world" could be expanded to include affecting the sun or celestial bodies. This could bring it closer to 4-C (star level), though this would depend on if the sun itself or its relation to the world is part of what gets destroyed.
3. The destruction results in a black void of nothingness. This might imply physical destruction but the erasure of space or reality itself. The feat could be interpreted as affecting more than just the physical structure of the planet and possibly points to higher-dimensional destruction (i.e., beyond 3D matter). If the void is universal in scope, it might scale closer to Low 2-C (affecting space-time on a universal scale), though that's questionable due to the MC still being able to time travel.
4. That would suggest the ability doesn't just destroy objects but can alter the fundamental cause-and-effect structure of reality. While "rewriting causality" is often used to describe the higher-tier, this alone wouldn't necessarily place the feat at Low 2-C unless it involves manipulating space-time on a universal scale. The fact that the MC can time travel suggests the entire space-time continuum hasn't been completely erased, keeping it below that level.
5. If the MC exists "outside of causality," this indicates that causality itself isn't absolute and can still be bypassed, suggesting that the destruction wasn't universal in the highest sense. However, the ability to affect causality can often scale feats higher than pure environmental destruction.

So I’d say the feat is from 4-C to 3-A (Environmental) depending on the exact interpretation of the cosmology.

 

[Astral_Trinity439]

1. Tsubaki is stated to be able to destroy "the world" (This is a fantasy setting so I'm not sure of the cosmology size.)
2. There is normally a sun that exists.
3. Her ability "Reset" which was what was stated to destroy the world leaves behind only a black void of nothingness.

This much suggests that the World is destroyed as a Space-time, leaving empty space behind.

4. Is described as "Rewriting Causality" with this ability.

The first scan here is, in fact, supporting that the world was destroyed as a space-time, since Causality is co-related to space-time often and the MC was in a state outside Causality after the world had been destroyed.
The second scan suggests the existence of a higher form of time; a hyper-timeline, to be exact.

5. I think it's below Low 2-C since the MC is still able to time travel, though he's stated to "exist outside of causality" so I'm not sure if that exactly applies.

The fact the scan explicitly stated "go back before the world was destroyed" where the scans before in point 3 and 4 suggest it was destroyed as a space-time, pretty much confirm the existence of a hyper timeline.


In conclusion, the world destruction would include the destruction of causality and be Low 2-C, while the MC's time travel will be Low 1-C. If you wanna low-ball the last rating, then likely Low 1-C.