The Callisto Protocol is a difficult game by design, right from the start. You’ll need any advantage you can get, as soon as you can get it, and most of those advantages will come from Reforger stations. Every Callisto Credit you can get might save your life, but it’s important to know when and where to spend it.
Here’s some thoughts on how best to spend your Callisto Credits as you’re making your way through Black Iron Prison.
More Callistol Protocol guides:
Chapter 1 & 2 Collectibles Locations | Chapter 3 Collectibles Locations | Skunk Gun Location | How To Turn On Performance Mode
Buy Low, Kill High: What to Buy and When in The Callisto Protocol
The Callisto Protocol is, effectively, a spiritual sequel to the Dead Space series, and like the first two Dead Space games, one of the easier ways to play the game is also one of its more counterintuitive.
There was a trophy/achievement for the original Dead Space, One Gun, that was unlocked by only ever using your default weapon. What was weird about it is that an all-plasma cutter run through Dead Space isn’t actually much of a handicap; in fact, once you’ve done it, it’s difficult to understand why other weapons are actually in the game. The plasma cutter does everything well except for crowd control, and you’ve got a couple of other options for handling that.
I’m bringing this up because, on my second run through The Callisto Protocol, I’ve been experimenting with a similar approach, and it works well enough that I’d recommend it to anyone who’s on the fence about their upgrade strategy.
In short: don’t buy any other guns. Don’t hoard resources; sell whatever you don’t need and spend the cash on upgrades. Pour all your money into maxing out the Hand Cannon ASAP, then improve the GRP and Riot Gun.
Everything Must Go
There’s a certain hoarding instinct that you develop over the course of playing a lot of survival horror games, and it’s something that you want to think twice about with The Callisto Protocol.
Especially in the first four chapters of the game, you’re stuck with only 6 inventory spaces for your ammunition, healing, GRP batteries, and valuables. You can drop anything at any time, but it’s still easy to end up carrying around more than you technically need.
Instead, it’s useful to get into the habit of actually using items, rather than banking them against a crisis. Keep yourself at full health, even if it means “wasting” most of an injector.
When you pass a Reforger, liquidate your excess inventory instead of holding on to everything. The more money you build up early on, the more you can spend on improving your firepower, and the better off you’ll be in the long run. Health injectors in particular sell for 100 credits apiece and are very common throughout much of the game.
Single Bullet Theory
You first get the Hand Cannon in Chapter 3. The first Reforger in the game has a resource chest next to it that gives you just enough credits to buy the Hand Cannon, which effectively makes it free to acquire.
Initially, its low stopping power makes the Hand Cannon primarily useful as a combo extender. You can use it at the end of baton combos to pull off high-damage skill shots, which target limbs or stop biophages from continuing to mutate.
With its damage upgrade, however, which is surprisingly affordable (600 credits, after the capacity/stability upgrades), the Hand Cannon suddenly has a lot going for it. Upgraded, it’s much more able to take off enemies’ limbs or heads, does significant enough damage that it can actually kill a target, and can penetrate its first target to strike whatever’s behind it.
The Hand Cannon’s final upgrade unlocks its alternate fire, which hits a single target with an explosive round. This spends 5 bullets at once, so it’s not something that you want to do casually no matter how well you think you’re doing, but it’s a one-shot kill against most standard enemies on Medium Security. 5 Hand Cannon rounds for one less biophage is often a worthwhile trade, especially if that biophage is a tank or spitter.
Later in the game, in Chapter 5, you’ll automatically receive the Riot Gun. This is a shotgun, which is useful for doing Shotgun Things like removing enemies’ kneecaps. In the late game, there are several mandatory fights where the Riot Gun’s high point-blank damage and magazine size are invaluable.
Once you’ve got the Riot Gun, throw cash into improving its standard stats, but don’t worry about its ultimate upgrade. While its alt-fire is a simple explosive round like the Hand Cannon’s, it doesn’t do quite enough damage to compensate for its high cost (4 at once) in Riot Gun shells.
Gravity Decides
There are a couple of distinct points over the course of TCP where you’re gently encouraged to do most of your fighting with the GRP. You don’t have to, but it will at least make your life much easier, as it’s a chance to instantly delete an enemy rather than having to take the time to beat it into jam.
As such, going at least halfway up the upgrade trees for the GRP is a massive quality-of-life increase, and it’s worth doing whenever possible. The third-level bonuses are incredibly expensive, so they’re likely best pursued on replays when you know exactly where to go and what to do, but you can hit the second-level upgrades without too much effort. It’ll pay for itself.
Point Blank Shot
One of the advantages to sticking to a small arsenal of weapons in TCP is that, like Dead Space, most of the ammunition you find throughout the game is randomized. Once you’ve got a particular gun, its bullets are added to the drop table from that point forward. As far as I can tell, no particular sort of ammo is hardwired to be rarer than any other kind.
If you’ve only got the one gun, of course, all the ammo you find will be for that gun. If you’ve got a full arsenal, the ammo you find will be spread out among all five weapons. This usually means you’ve got five half-full guns instead of a solid supply of ammo for two. Worse, it means you might be thinking about using the Tactical Pistol, which feels fairly useless at time of writing.
By deliberately keeping your arsenal slim, and restraining it to a couple of go-to weapons, you end up getting showered in ammo for those weapons after roughly the halfway point of the game. While both the Assault Rifle and Skunk Gun have points in their favor, for an initial run at TCP, you’re better off keeping things light with just the Hand Cannon and Riot Gun.
On Rails
Something you’ll notice if you buy one of the extra weapons, such as the Skunk Gun, is that TCP‘s 3D-printed guns are handled in an odd way. You effectively have two trigger rails on you, one short and one long, and your currently active gun is whatever Jacob has attached to your current rail.
Whenever you switch between short weapons, that means Jacob pulls apart the first gun, then snaps together the second. It takes a little while, which can be anywhere from inconvenient to lethal if you’re in the middle of a fight.
It makes life a little easier if you stick with having one long gun (Riot Gun, Assault Rifle) and one short gun (Hand Cannon, Tactical Pistol, Skunk Gun) on you. It means that if one gun runs dry in the middle of a fight and you have to switch, you actually can, rather than having to watch Jacob abort the reassembly animation whenever you have to dodge.
Especially towards the end of the game, you can save yourself a lot of headaches (or, well, split skulls) if you take a couple of minutes occasionally to make sure both your short and long guns are loaded and ready for quick-selection.