Eredin fight bug?

[Hayashi.226]

I'm not sure if this is a glitch/bug, but in my first playthrough I was able to defeat Eredin without too much difficulty. This time around however (NG+) I'm battling him aboard his ship and Geralt doesn't do any damage to him whatsoever - even when I've backed him into a corner and I'm wailing away on him with fast attacks. So much so that Aerondight went from 100% condition to 40% lol.
Is this a bug or just my poor fighting skills?

 

[Draconifors]

Do you have enemy upscaling on? Some people have reported it causing issues with Eredin (and a few other enemies).

Other than that; I found the same bug on the GOG forums. The thread is full of nasty drama, so I'll quote user Cathris instead of linking:

The bug you reported is actually a pretty old one, happened to me too once, on my second run

That particular boss will "gate" away and drag you with him when he reach certain health thresholds, unfortunately if you hurt him too fast, the script may fail to trigger. You'll need to reload a save just before Ciri sequence and when Geralt face him, go easy on him, don't hurt him too fast, stun him with the charm and slash with the blade only once or twice before jumping away

Of course you can use a different tactic if you want, but heed to the same advice, if you hurt him too fast the final battle become bugged

Sorry but there is no other solution i found, i know is somehow ridiculous to have to go easy on the final boss, but so it is

As a consolation, after he "gate" you away the first time, you should be able to hammer him hard and the script seems to work properly usually, so there is at least that

 

[Hayashi.226]

Thank you. Went back right to the beginning of "On Thin Ice" and replayed the whole thing, and took my time with Eredin. Finished the main quest!

 

[Caleb_Mooneyham]

Do you have enemy upscaling on? Some people have reported it causing issues with Eredin (and a few other enemies).

Other than that; I found the same bug on the GOG forums. The thread is full of nasty drama, so I'll quote user Cathris instead of linking:

I know this is late, but I am just now playing this game for the first time (again... I know im late...) but I had the same issue... I am running a sign build and I kinda blast through enemy combos and don't let anything finish.. I hit a block twice where he stopped taking damage, but If I stopped and let him beat on me for a little bit and finish those combos, the game mechanics would trigger.

 

[SigilFey]

That sounds more like something mod-related. Are you using any mods, or have you ever used any in the past?