Hel-Travellers are fearsome, elite opponents. They're a variation of Travellers, and so the same tactics apply.
Travellers come in two forms: one has a huge shield on its back, and the other doesn't. There isn't a whole lot of difference in each fight, however — it's just that attacking the shield will cause Kratos to recoil, making the whole affair a bit more difficult.
Travellers come equipped with a huge sword which they just love swinging. Their main combo consists of several swings in succession — all of which can be blocked or parried — and an unblockable attack is usually waiting at the end. A Traveller's unblockable hits can be dodged fairly easily once you're used to the timing — but get ready to eat some big damage if you don't get it right.
The bottom line here is that you need to watch Travellers very carefully. One unblockable attack sees them fly forward with their blade stretched, and it's fast. A quick sidestep or roll is enough to get out of the way, but you need to see it coming.
The other trick up a Traveller's sleeve is the magical blast that happens after they hold a skull aloft. To stop this inescapable shockwave, you need to hit the skull with a ranged attack — a good throw of your axe will get it done, but you'll have to be quick.
Travellers are basically minibosses, and should be treated as such. They require patience and concentration if you're to best them. If nothing else, just make sure that you don't get hit by the unblockables, and you'll be on the right track. Remember to attack only a few times before backing off, and repeat.
How many Hel-Travellers 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.