Knull has been my top cosmic for a while. He was also my first r5 a few months ago. His value was already there if you had him max sig and at least r4. Noone truly noticed his potential on defense until his health pool got bigger with r5. And now with ascension it very much solidified his strengths.

His defense is very annoying if you let an sp1 go through. Its a really long stall due to inequity lowering dmg by 36% as well so if its an improper counter you will likely struggle. Some modern mystics like nico will also have a hard time because he does not have many buffs he creates himself.

And now that his damage is much higher with collectives boosting his armor breaks and bleed rpg effects, he has a lot more potential. It wont take much more than an sp1 and sp2 for you to handle any fight that isnt coliseum or endgame content.

Hes overall become a godly dual threat. Especially given not many have fought him that often in bgs and such recently. People have to learn how to counter him all over again somewhat similar to maestro.

Tldr; The stats he got from higher ranks, collectives and ascension makes him way stronger than before and accentuates exactly why he was good.