As a revision was being made for Mario pages opting for them to be changed from "Large Star, likely Multi-Solar System" to just "Multi-Solar System", Dino Ranger Black didn't want to lose the Large Star level calced feat. So as a compromise, I offered to make a respect thread for the Marioverse regarding tier 4+ feats so that it wouldn't be lost. This is my first respect thread, so don't be so harsh if I mess up on a bit. c:
The popularly noted feats are feats regarding the Power Stars themselves.
In Super Mario 64, all of levels that you go to that are within paintings or similar things are realms created by Bowser using the Power Stars, and in Bob-omb Battlefield, you can see that there is a star with much space around it, and in Tiny Huge Island, Wiggler says that he can see stars through his ceiling at night, implying that there is a sky full of stars in this realm at nighttime.
Further evidence of the power of the Power Stars is Rosalina verifying that they become actual stars. Black holes turn into power stars under certain cirsumstances, which the size of said black holes were calculated to yield this much potency.
Here, Antasma is shown manipulating the Dream World to an unknown degree, albeit without the Dream Stone.
Millennium Star, the final boss of Mario Party 3, is capable of creating a background full of stars. Any of the cast can defeat him.
I think this sums up most of the relevant tier 4 feats in the series, and I think most of the cast can now safely be 4-A without worry.