Zeugl on FCR Witcher difficulty - impossible?

[kittysphynx]

Hiya. I'm close to beating this game on as hard a setting as it can be, but I just ran into a wall. Namely, it's the Zeugl fight. Even on the Witcher difficulty, I managed to defeat the Beast and Koschey in a relatively normal amount of tries (Quen was a big help all the time), but Zeugl is the first time when a fight seems impossible to win - not even if I hope for that sudden stroke of luck where a powerful boss doesn't hit me once due to RNG.

I have Silver Strong leveled up to 4, and Group to 2 (never needed it before I started the fight :/), Quen fully upgraded, all four universal stats fully upgraded (and all mutagen skills), too. Moonblade with the most powerful rune doesn't do very much, sadly. I haven't used Igni at all, and I fear it was a bad choice to put points into Heliotrop instead.

I drank Tawny Owl, Petri's Filter, Full Moon (making me have effectively 110 HP - max on this difficulty) and Golden Oriole, then meditated, and then drank Swallow (Rubedo) and Blizzard (Nigredo), topped it up with some food. I sometimes manage to come out of the first tentacle phase relatively unscathed (if I'm above 70% HP). I try to pop a Quen and do the charged strong attack on Zeugl - it deals 31 damage, then I manage to stick about 1.5 of that if I do 3 Strong attacks and the Zeugl doesn't kill me literally in 3 hits.

The farthest I ever got was the 3rd head attack, but until then, he usually kills me with 3 attacks or the tentacles whip me to oblivion (if I try Group Style, I often miss 5 times in a row and the bonus to parrying and dodging seems negligent, so I try to pick them off with strong, killing a single tentacle in 2 Strong attacks OR 3 Group attacks). I can drink 1 White Raffard's Decoction, but then I'm at 38 Toxicity and another one would be debilitating, but often when I drink it, the tentacles immediately take off the HP I just regained. Or I drink it before attacking the head, but then I usually miss out on the ~70 damage I could do on a perfect cycle. Healing up before attacking it or using Quen hardly seems efficient anyway, seeing as it can take off my 110 HP in seconds if I'm not ridiculously lucky. I've tried running around for Swallow to heal me up, but I get hit too often to get any meaningful progress in that.

Getting benefits from Quen and Blizzard seems to rely on a coin throw each time I load a save (as was the case before - seriously, sometimes it's as if the game only realizes I have so many bonuses to dodge and parry on the 10th try on a tough enemy). And Triss is, obviously, useless. She doesn't really go down that easy, but her spells don't do any meaningful damage, she seems to have forgotten how to heal after Act III (the sole thing that would help me lol) and doesn't reliably aggro the head or tentacles.

I'm not whining, mind you - but that's all the meaningful info I can think of, are there any tricks I could use (I'm already using the trick where if you start the attack that would kill an enemy and run away, they die after a delay with one less chance to hit you)? I have the potion to set the difficulty to level 4 out of 6, but I've had less successes with it that without it. Any bombs that could help me out? Am I doomed because I never used or leveled Igni?

For reference - Koschey took about 20 tries, and I may have hit 40 today on Zeugl with no progress to speak of. I'd like to complete the challenge, but I've already made peace with the perspective of abandoning the run just shy of the end. :/

[Harulem]

Very late to the party but in case anyone else has the same problem, here is how I did it (FCR in witcher difficulty).
The solution is the dragondream bomb. It is pretty lackluster and almost a hack, but there is no other solution to my knowledge.
This bomb boosts the damage of igni by a significant margin, so much so that you can one shot anything in the game, including the kikimore queen, the king of the wildhunt, dagon, etc ...
Just drop a lot of dragon dream bombs were the Zeugl will spawn, hack the tentacles, zeugl appears, one cast of igni, insta kill.
I needed 4 bombs with igni maxed,without igni buffed up it will take a lot more, but it is very doable. You will most probably have to reload a previous save to stock up on materials though. Kalkstein sells them.
Be aware that the final fight against the grandmaster is 10 times worse than this one.
I am convinced it is completely impossible without abusing dragon dream.
And you will also probably need Yrden at a decent level to stun him long enough to drop the bombs since you are trapped with him in a small circle.
Yrden is also a godsend against the king of the wildhunt and his specters.