Perks will help you make the most of the weapons in Horizon Zero Dawn, as will modifiers that target different elemental weaknesses. But while these upgrades are important, you'll want to have the best base weapon underneath it all.
At the most basic level, purple means good, but some of the weapons from the Frozen Wilds expansion (which is included with the PC version of Horizon Zero Dawn) and the Hunter's Lodge Trials are good enough that you might want to be a little bit careful about what you spend shards on upgrading.
If you're still getting started in Horizon, here are the items to look out for, and what they're best for.
The Tearblaster is a weapon designed with a clear purpose: It rips armor off your enemies. It can tear the cannons off the backs of the biggest creatures, and leaves them open to damage—from another weapon. The Tearblaster itself can't cause much damage, so be prepared to switch it out once you've opened a vulnerable spot up. This is basically a playmaker weapon, but you need to find something else for the kill.
Further down the list, there’s a lot of weapons from the Hunters Lodge trials; this is a crucial weapon for winning those trials.
Part of the Frozen Wilds expansion, the Improved Stormslinger is unlocked during a side quest in that storyline (it's called "Geared Up: Stormslinger").
The Improved Stormslinger is the most powerful weapon in the game in terms of raw damage, and is especially deadly when up against foes which are weak to electricity. It takes a long time to unlock so is not much help to beginners, but as you make your way through Horizon and take on the tougher enemies the Frozen Wilds has in store for you, you’ll need the Improved Stormslinger by your side.
Banuk Powershot Bow
With the right upgrades, this weapon—also part of the Frozen Wilds—can easily become one of the best in the game. It’s already one of the strongest weapons without any modifications, and has the furthest range of any bow Horizon has to offer.
The Banuk Powershot is best used for airborne enemies—there are slightly better weapons for the big, roving machines—but the flying foes are probably the scariest enemies in Horizon. You'll be happy you have one.
Lodge War Bow
You earn this bow by completing the Hunters Lodge trials, so while it’s a great weapon, bear in mind that you’ll need other great weapons in order to unlock it. Once you get Aloy’s hands on it though, expect this to be the bow she uses the most. It has devastating power, and offers a big boost to elemental damage. It also has built in bragging rights, since you need some skills to even own it.
Shadow War Bow
Shadow War Bow is 'your bow' and the Lodge War Bow is 'the bow she tells you not to worry about'. It's basically as good as the Lodge War Bow, but has worse elemental effects, and so once you unlock the Lodge version, the Shadow one isn’t going to get any attention. However, to actually earn the Lodge version, the Shadow is pretty much required weaponry. Basically, you'll use it extensively to unlock its replacement, then show your gratitude by never using it again.
As you've already seen, the Frozen Wilds contains some of the best weapons in Horizon, so it should be no surprise to see another one make this list. The Improved Icerail is an ice cannon, able to freeze enemies as well as damage them, and has a hell of a kick to it. However, it’s basically a shotgun in a game designed for a bow and arrow. Devastating at close range, but you'll probably want to keep your distance for most of the game, which stops the Improved Icerail from being a truly essential weapon in Aloy's arsenal. Still, it's cool.
Lodge Blast Sling
You can play through most of the game without ever really using a sling, but if your playstyle leans towards them, you’ll definitely want the Lodge Blast Sling. Like the Lodge War Bow, it comes via the Hunters Lodge trials. It can launch vials and proximity bombs towards enemies, and can be great for dealing big damage in one go, although it's nowhere near as accurate as a bow and arrow. However, the Lodge Blast Sling has the best handling stats in the game—close to double its nearest competitor. That means most of the drawbacks of a sling aren't present here, and while it’s no bow and arrow, it's no slouch either.
Much like the Improved Icerail, the Shadow Rattler’s effectiveness is hindered by the fact that it’s most effective at close quarters, and Aloy (and the game) is built more for ranged fighting. It packs a mean punch, but probably shouldn’t be used that often. However, if the Improved Icerail is on the table, then the Shadow Rattler—which can be unlocked much earlier—must also be in contention. Just know that you're picking a tougher playstyle with it.
Much like the Lodge Blast Sling, how much use you'll get out of this depends on your playstyle. A Ropecaster isn't an essential Horizon weapon the way bows are, but if you're going to use one, this is clearly the best.
You'll probably find yourself growing out of using Ropecasters as the game goes on, because they use so much wire and aren't particularly worth the resources. In the late game though, Ropecasters can be incredibly useful for tying the biggest machines down.
It clearly isn't as showy or as powerful as the other weapons, but Aloy would be pretty damn lost without it. Not only can it be used to control machines, it's also a fairly decent club in a pinch, if you’re going up against weaker foes or if you have an airborne foe tied down and need quick, powerful hits while conserving resources. Don’t rush in and try and club a Thunderjaw to death, but don't completely underestimate Aloy's melee skills either.