The new iteration of Warworld
https://ibb.co/Bg4p5vQ
It also refers to the first appearance of Warworld( DC Comics Presents 28)
Superman one-shots Ace when he goes serious
https://ibb.co/M8JKbPS
https://ibb.co/VwMB6Wc
Who could deliver a punch that Flash thinks is fast in previous issue
https://ibb.co/RYF1Nb9
https://ibb.co/BzrwWmk
Depowered, Superman takes down huge monsters without any weapon
https://ibb.co/PYqHFpn
https://ibb.co/5KZnpQg
https://ibb.co/89XftgM
https://ibb.co/3C5gbMD
Flash casually beats elite magicians
https://ibb.co/DVr0XHd
https://ibb.co/TbgqGDP
https://ibb.co/PzD0mZz
https://ibb.co/9wL6dBw
Again, confirmed Flash immune to Eclipso's influence
https://ibb.co/XX1trff
When Reed got his powers he used those (mostly subconsciously) to increase his intellect by subtly altering his brain structure. It's the same thing the Maker does but to a lesser extent. This turned him from a "normal" genius that can build rockets to a supergenius that can do basically anything, given enough time.
Thus, if Reed's intellect gets messed with he should be able to restore it, assuming his powers still work.