One of the things that players can't do in Horizon: Zero Dawn is rely on small arms fire, SMGs or assault rifles to help them out against the robosaurs. However, that wasn't always the case. It was recently revealed that Guerrilla Games did in fact have plans to add machine guns to the game.
According to a recent interview that Neil Druckmann from Naughty Dog conducted with Hermen Hulst, the studio head from Guerrilla Games, we learned that the early prototype of Horizon: Zero Dawn featured weapons similar to that of Killzone. Gamespot plucked the relevant quote from the 24 minute interview that was posted up over on the official PlayStation YouTube channel, where Hulst explains...
Hulst goes on to say that, conceptually, guns in Horizon didn't work because the game takes place in this beautiful, idyllic location and it seemed as if guns were far too disruptive for the mostly peaceful tone they were going for with the game. Hence, they had to reconsider the kind of weapons that were at the disposal of the players. So, they decided to reduce the weaponry of the enemies to that of the bronze age, with the exception of some of the special mini-boss enemies from the Carja tribe who carried around turrets stripped from some of the older war class machines.
For the most part, Horizon: Zero Dawn players utilize bows, arrows, and tripcasters. There's also a spear for up-close melee attacks and plenty of traps as well.
In some of the older concept art for the game, they also outfitted the main character with flintlock weaponry, presumably as a means of killing other human characters quickly at moderate ranges when the bow and arrow were a little too slow on the draw. However, even the flintlock pistol didn't make the final cut of the game.
This is not to say that there are no guns in Horizon: Zero Dawn that players can use. Instead, it just means that the guns that are available are specialty weapons, specifically heavy arms that are cumbersome to carry around and only available in limited quantities. The majority of the game will instead be played using different types of upgradeable bows and arrows.
This wasn't an easy thing for Guerrilla to tackle in Horizon, though. The reality is that they had to completely overhaul the engine and tools for the game because they were accustomed to making first-person shooters -- they did come from a 13 year background in making Killzone games, after all.
They designed the Decima Engine to help with designing the necessary tools and pipelines to bring Horizon: Zero Dawn to life -- it's also the same engine powering Kojima's upcoming Death Stranding -- and in turn a world that's teeming with beautiful natural locations for players to explore and lots of robo dinos to fight. Of course, this also meant stepping away from their heavy focus on guns and assault rifles, which is what the Killzone series is known for.
It all seems to have worked out, though, as Horizon has been one of the big sellers for the early half of 2017.