Cursed Nokkens are essentially just stronger versions of Nokkens. As such, the same tactics apply.
Nokkens are small creatures that can empower nearby enemies with their unsettling, magical chants. Once discovered, Nokkens have a tendency to flee, as they have low health and very little in the way of self defence.
Nokkens should always be your first priority when you hear their horrible little chants. Their magic will make their allies invincible, so the Nokkens must be destroyed before you can effectively fight other foes.
Tracking down a Nokken is a case of following the direction of its chants. Visually, this direction is hinted at by the auras of the enemies that the Nokken is empowering. Said auras will point towards the Nokken's location.
Once you've found a Nokken, waste no time in killing it. Nokkens can strike back with their claws, but they shouldn't even have a chance to do so once their position has been uncovered. They may also try to flee, but they're not that fast, and you'll be able to follow them with relative ease.
How many Cursed Nokkens have you smashed into submission? Be sure to check out our full God of War Ragnarok guide for information on how to beat every enemy, and much more.