Infinitely dividing their power is not "word play" no matter how much you repeat it, it's what they literally did to be able to enter the world without it going poof because of their presence and even then it was a close thing, with the group still being much more powerful than Othinus was and perfectly capable of destroying the universe with ease if they wanted. The novel is pretty clear on that front.
Then comes Aleister, who takes over Zombie's spell and nerfs them even more, taking away so much of their power that they lost access to their Phase powers and became shadows of their former selves. Even then that was because how the spell nerfed them by splitting their existence, as Nephthys (who by her particular nature as a Magic God specialized in cutting, splitting and separating her own power) shows they still had enough juice/power to swap Phases/destroy the universe once, they simply couldn't use that remaining power properly. As Niang-Niang said:
"We're not the ones this is a real problem for. I just can't figure out what 'he' was thinking by dragging us into the real world in this incomplete state. You could say we're in a state where we can destroy the world but lack the strength to recreate it afterwards."
So you should see how far above they were over Othinus if after two massive nerfs they still had that amount of power left. In NT13 they basically had 1/∞ or less of their original power left, because as far as we can tell Aleister cut their access to everything else.
Trying to bring up World Rejecter "overpowering them" shows that you don't understand how it works or what went on in NT13. The Magic Gods were basically almost completely depowered by that point, that is why they were using more down-to-earth spells, like High Priest using his dirt manipulation magic or Niang-Niang using her Pao Pei, so trying to argue this should affect their tier pre-nerfings is ridiculous. Even if they had access to more power (say, if they still were at Othinus' level of recreating the universe hundreds of billions of times) I doubt they would had tried to stop WR once they started being affected; as you can see when Kakeru attacks Niang-Niang and Nephthys the World Rejecter is basically giving them what they wanted in the first place, so why fight it? Even Nephthys who watched what happened with Niang-Niang felt jealous of her and also felt a mixture of fear and joy when Kakeru turned his attention and right hand on her. His power doesn't work by overpoweing people. It worked on the Magic Gods, IB and the Anti-Art Attachment powered by Aleister, but failed to work on Patricia (normal human girl, even with Sample Shoggoth), his harem (so far all low tiers or actually powerless) and Noukan (normal dog). Tell me, were those people stronger than the Magic Gods, IB or Aleister? I don't think so.
Just in case you missed the several explanations NT14 gave: Kamisato Kakeru is a joker character that doesn't really play by the same rules the rest of the universe plays by, just like Touma. That's the kind of power those two wield. If in the future we add a tier list to the verse page those two should be separated from everyone else in their own tier, Normal High School Boy Tier, only rivaled by the mythical Normal Magician Tier and Vampire Tier.
And the one ignoring what the novel actually says are you, since you are dismissing what True Gremlin actually did as word play for no apparent reason. Thor and Carissa are fine where they are. Really, the only problem I saw happen with Thor here was as misunderstanding because of the ambiguity of the word "world"; which in Thor's case was referring to Earth, not the universe as some believed.
