God of War Ragnarök

It is worth adding that here you can encounter any of the berserkers as a boss - according to the video guides, the first one is Hartrefil the Soulless, but there is an option that at higher difficulty levels any of the berserkers can randomly pop up.
To simplify the battle itself, it is worth quickly completing 7 chosen ones of Valhalla - preferably on the blue and yellow rifts, and in the Aegean boat - so that time is not wasted on making the opponents more difficult.
Hartrefil himself has a limited set of attacks - all but the red jump attack can be parried with a shield. The best ones here are the Guardian's shield, which will allow you to immediately counterattack after parrying, and thus interrupt his attack series, and the axe, with features for accelerated ice gain - after a counterattack with a shield, we perform the "Ice Pride" technique (I play on the old version of the layout - therefore ) - thus we accumulate a full charge of ice, activate + - with this scheme, in 3 repetitions, I knocked down to 90% HP - in the end, I finished him off quickly with runic attacks. Also, try to keep the axe "charged" with cold before parrying - then "Ice Pride" can be activated in a simplified way through a powerful blow with a "charged" axe , then just two weak blows and heavy - this method gives slightly more damage, more freezing of the enemy and slightly accelerates the growth of the "ice" level