Horizon Forbidden West will introduce Aloy to quite a few new weapons that she never saw during her adventure in Zero Dawn. One of those types of weapons is Spike Throwers, which are essentially spears that you throw that have a special effect on them. Here is how to get the Prototype Spike Thrower.
To be able to get the Prototype Spike Thrower in Horizon Forbidden West, you will first need to complete the early story quest, To the Brink, and get at least partway through The Embassy. After the merchants are allowed to open shop again, you can find Delah and Boomer in the western portion of Chainscrape. Talk to them, and you will start an Errand called A Bigger Boom.
To complete A Bigger Boom, you will need to collect three Charger Horns and a Fanghorn Rib. Luckily, you can track the quest and be led exactly to where you can find both.
For the Charger Horns, you will need to shoot the horns off the machine before you kill it, or it will be destroyed. We recommend first sneaking up to the group of chargers and scanning one with the focus. You can then cycle to the horn parts to light them up for you. For our early game bow, it took two shots to each horn to knock it off onto the ground.
As for the Fanghorn, all you need to do is kill it. It will be patrolling a small area accompanied by two Scroungers. We recommend first sneakily taking down the Scroungers and then focusing on the deer-like machine. It is weak against ice, so first hit it with your Frost Blastsling or another ice item to knock it on the ground. Run up to it then and finish it off.
Once you have gathered your three horns and rib, return to Delah, and she will make the Prototype Spike Thrower and give it to you. When equipped, you can not throw the spikes
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