For me (having the luxury of a DoT Build) it all depends on the combination of foes and how many are dead when he engages.
Grava plus Zantarin? All good.
Grava plus Moosi/Benn´Jhar? Okay…
Grava plus Kaisan/Mad Queen? WTF?
Valdaran is really annoying, too, in the combination because of his stuns when you kite.
Some can, most can’t even see them among all the special effects, some casters just can’t take hit when kiting (spam-casters).
Overall his Nullification mechanics feels like Zantai is trying to unplug your keyboard while you are playing but you can’t take your hands off to stop him so you gotta maneuvre awkwardly around your pc with your office chair trying to block him and eventually shoo him off with an ancient Hebrew nursery rhyme.
And what about pet purifiers? do they count among the “strongest tankiest archetypes”?
Perhaps it is less about Grava being OP and more about certain builds having problems with certain bosses or boss combos?
Like, the ones I dread the most are Kaisan and Benny for eg.
My first encounter with Grava in SR was with Aegis SB on wave 76. I kill him with few deaths, kiting from him, Kuba and Benni. But second time, he destroyed time and time again my tanky Deathmarked Blademaster.
Like WTF can do with typical DW build? Avoid every single nullification in 6 or 7 consecutive tries? Or kite the hell out of him? But Belgo for instance don’t have even DoT damage. In SR as melee, you see Grava or Slathassar, you just restart. Cold BM can kill Kuba for example, but Grava is too much. And ofc you have other bosses at same time, so it’s much harder than campaign.
Pop an Aether Cluster and pray, that the one Sanctified Bone is enough to kill him fast enough. 
Elemental Purifier is naturally very tanky. I don’t know how strong it is with pets tho. I guess still tanky if you are managing Shard 75 with it.
Every Belgo has Santified Bone in chest, man. Same with Deathmarked BM.
It isn’t. Not with pets. I don’t have the char anymore, but I can make it and send you the save file if you want to test it for yourself.
No, thanks, I don’t play pet builds at all. But I guess it’s a gimmicky build so it’s ok for it to be less tanky as synergetic pet builds or synergetic Purifiers. Because Elemental Purifiers are strong as fuck atm.
Yeah, basically it uses pets from items along with Bysmiel rings + Mindweaver for Conversion into Ele and then use the RR from Censure, mines and BWC.
But the point I was making again was how it could still take down Grava even though it was neither strong nor tanky. But if it was Kaisan in its place, I would have had to restart. So, if Grava needs to be toned down, so does Kaisan, so does Anasteria, So does Slathasaar etc.
You know that emoji ( ), don´t you?
Pierce-, Aether- and Chaos-Melees will have a hard time because of no DoTs. You have to engage him, make as much damage as you can, disengage…repeat. And with all this proccs around, his aura, the other foes…he is surely a real PITA.
Surely you can quit like Nery said. I do this after two tries vs. Mad Queen.
Again, man (woman!), your example is a bit irrelevant. You have completed boss chunk with Grava with a gimmicky build. Does not mean Grava is okay. Or the fact that you can’t beat Kaisan with a gimmicky build - does not mean that Kaisan is not okay.
Let’s not judge difficulty by god-tier builds’ performance or gimmicky builds’ performance.
Ok, but then I don’t get your point either…
Because first you say my build is OP
Then you say my build is gimmicky
But then you say Grava is OP
Why is Grava OP if you can even do it with a gimmicky build?
My point is that the balance in SR is off. And Grava is grossly imbalanced on top of that.
Yup. But problem with Grava, is not just him nulls you. He also one shot kills you. So at high shards, he kills me through aether cluster even. According to Sir Spanksalot Grava nulls your mirror as well as Blade Barrier. So unless that have been changed, his mechanics are beyond unfair and broken.
I have written already. SR Grava is too strong. Too much fumble, too much melee damage, too much with his Nullifier. He outperforms all nemesis and bosses in every single way.
I just showed you it is not…
Or are you saying that a Pet Purifier is stronger than every melee build that is not Warlord?
No you did not. You showed me a screenshot of a gimmicky build completing Shard 75. That really doesn’t say anything.
What do you think is the thing dead on the screenshot?
And if the problem here is that you can’t believe my claims, I just offered you a save file to test for yourself.
Man (woman!), this is not logic works 
. I am telling you that the balance is off and Grava is off based on my experience with pleuthora of different builds - strong, medium, weak-ish, melee, casters, dot, different class combos, different archetypes. You are trying to make the case based on the fact that you managed to complete Shard 75 with a gimmicky off-beat spec. There are so many factors here: like how tanky is that spec really is, how many times you have died, did you get lucky mutators, did you use clusters/potions, were other bosses hard or you could isolate Grava 1on1, etc.