Hraezlyr

You'll encounter this massive lightning dragon on the way up the summit during the journey quest Chapter 5: Inside the Mountain 3. After exiting the cave the dragon crawled out of, you'll find Sindri being attacked by the dragon. Run to the left and hop at the back of the dragon to start the dragon slaying sequence. Once Kratos finds himself inside the dragon’s mouth, keep attacking with your axe until it spits you out in the open battlefield.

Once the battle starts, take note of the location of the shatter crystal pods. You have to throw a shatter crystal while the dragon is attacking with its lightning breath and summons lightning strikes to your position. Once done correctly, the blast will damage its heavily armored head, revealing the softer tissue underneath. This will also cause the dragon to get stunned temporarily and fall down to the ground. Use this chance to perform runic attacks to deal as much damage as possible within a short span of time. After the dragon recovers, pick up the healthstones it drops and track it as it repositions.

During this sequence, it will start attacking with its claws. When it slams its claws, block the shockwaves that will be produced. Counterattack after evading its melee attack, preferably with runic attacks as well or normal heavy attacks.

After a few melee attacks, it will resume using its ranged lightning breath attacks. You’ll have more than enough time to avoid this blast. There’s a damaging residual energy on the ground as well after this attack so don’t attempt to step on it until it dissipates. Pick up a shatter crystal again and throw it while it’s blasting its lightning breath. You have to be close enough so time your throw as soon as you get out of harm’s way. You should aim to the already damaged part of its head. Successfully detonating a shatter crystal there will stun the dragon once again.

The dragon will reposition again after recovering. Pick up the healthstones it will leave behind and prepare for the next part of this long battle. It will perform a few melee attacks again so prepare to block/evade and counterattack when you can until it resumes its lightning breath attack. Repeat the same procedure to knock it down again. Perform a few more attacks on its vulnerable part until it recovers.

It will reposition for the last time. Like before, you have to react to its melee attacks until it resumes using its lightning breath. This time, instead of firing it in a straight, predictable line, it will start spraying its blast in various directions while also summoning lightning strikes. There’s only one shatter crystal pod remaining. Time your throw when its using its lightning breath. It may take two shatter crystal explosions to knock it down this time. Once it gets knocked down, perform your runic attacks until the prompt for Atreus to lower the crane appears. Press square to issue the command. Smash the circle button once prompted to stab the dragon with the large shatter crystal to finish it off.