There are loads of twin-stick shooters, and there are a ton of roguelites. Using undead monsters as your antagonists has also been done countless times. Combining all of these into one game isn't that new, either. If you're the developers behind Calcium Chaos: Derailed, you do what you can to get people to pay attention to your game, which contains all of the aforementioned elements.

The story starts off simply, with a guy named Amir sitting at home and playing video games. Without warning, a train barrels through his house and narrowly misses him. Amir goes outside and finds that Robin, the train's driver, is ecstatic that the old train can run at all. Before he can question why a train wrecked his house, Amir is informed that the world has been under siege from living skeletons for at least a week. With the promise that his house will get repaired afterward, Amir accompanies Robin on her quest to find and defeat the skeleton necromancer while also picking up allies and survivors along the way. As you can tell from the opening level, the story is silly but not absurd. The environments are clean in that there's no debris anywhere. The characters are jovial and likable, but they aren't quick to joke around. Overall, you're looking at a game with very lighthearted vibe.

As alluded to before, the game is mostly a twin-stick shooter, albeit one that uses a trigger pull for firing instead of just aiming the stick. You have a dodge ability to dash over gaps and go through enemy fire, but the dash distance is far enough that you can accidentally fall into pits in the heat of a fight. You can find a bevy of weapons and items, but all of them are pretty unconventional in their appearance. The first weapon you'll find is a wrench that acts like a boomerang, and you'll find other things like chickens that shoot explosive eggs, soda that acts like acid, or a party popper that fires like a shotgun. Sandwiches act as health bar extensions, energy drinks slightly increase your movement speed, and a ghost can make you invincible for a short amount of time. Like the story, these things give the game a more playful tone.

The big hook comes from the ability to combine weapons to create something interesting. You choose one main weapon as your base and at least one other weapon to act as a supplementary ability. The same combos create different weapons depending on that base, so using a toaster base with a playing card, for example, has you shooting toast that leaves playing cards behind. Using the playing card base with a toaster means shooting playing cards in a spread pattern. Adding more supplementary weapons beef it up, so you can create something deadly like a chicken with eggs that leave behind pools of soda or a temporary rapid-fire feather turret.

The weapon combination mechanic becomes a big source of fun because the combinations are numerous when taking into account the plethora of weapons. When you reach the end game, you can combine six weapons at a time to create something that can decimate an enemy in seconds. What makes this system more appealing is the fact that you can keep rearranging combinations without any penalties or cost. Provided you're near a workbench or have a portable one on hand, you can spend as much time as you need on this task, and the only real lament is that the game has no way of keeping track of the combos, and it doesn't come up with any cool names for them.

Initially, the roguelike features seem fairly standard. The level layout is randomly generated, while the rooms are selected from a small pool of pre-made configurations. The items and weapons are randomized, as is the map, which determines the kinds of rooms and shops you'll come across during the trip. The train you live in has a few permanent upgrades you can buy with the cartons of milk that were converted from the weapons and bone shards you collected in each level. For veterans of the genre, it's all familiar stuff.

It doesn't take long before you discover that some key elements of the roguelike genre are missing. For example, dying only sends you back to the previously cleared room in a level, and there's a small currency loss as punishment. Death also doesn't randomize the level layout or room configuration. You never lose any real progress as far as the overall campaign is concerned, and you can even go back to previously cleared levels to grind out what you need to fully buy all of the game's power-ups. Enemy randomization also isn't very good, so you're likely to see all of the enemy types for that stage in three rooms. In practice, these things are large enough that many players will feel like the game is more of a standard twin-stick shooter with a smattering of roguelite elements to spice things up.

Calcium Chaos: Derailed features multiplayer for up to four players, but this is only local multiplayer since no online option exists. What's interesting is how the game behaves when more players are present. There are more starting bags to match the player count, and each bag's contents are randomized. The items in the world are only given to the player who picked it up, but the items and weapons can also be dropped so other players can grab them. Hearts are shared among the party, so a person who's already at full health doesn't hurt the rest of the players by nabbing all of the health. Downed players can be revived with a decent amount of health that isn't taken away from the player who revived them. The bone shards are shared among all players, as are the permanent power-ups from the train, so there's no need to fight for those resources. Overall, it's a rather friendly multiplayer experience that becomes chaotic once you find the right weapons to use.

The main campaign can take a little under five hours to finish, especially if you're playing through with other players. While there is no New Game+ mode present to let you fully kit out your party, a new Hardcore difficulty makes the game lean closer to being a roguelite, since it features permadeath. However, even this feature is toned down because you have a few lives in your stash before permadeath goes into effect, and you can still save in between levels, negating the effects of permadeath in the process.

The presentation feels pretty casual. The music feels pretty light, with none of the tracks producing anything with any high intensity that is expected from big, crowded fights. The sound effects and voices are fine, which are nothing more than grunts. The graphics may remind someone of old Flash animation due to the bright colors and simplicity in movement, but it's still good. The only issue one is that there's slowdown when you suddenly fill the screen with enemies and weapons. Slowdown is a rarity nowadays, especially for those with very high-end hardware, so seeing it can feel a little disappointing while also providing a nostalgic vibe.

Those who want to experience the game on the Steam Deck would expect it to be a fine fit for the device. The full 1280x800 resolution is supported, and the game menu works perfectly fine. Get into gameplay, however, and the game demonstrates some wildly inconsistent frame rates. You could be running around at 60fps for a few seconds before the game decides to pause and drop you to 40fps. You may jump back to 60fps, but the game will decide to go into 5fps or less for a few moments before going to 30fps then returning to 60fps. The problem with this inconsistency is that there's no rhyme or reason. The issue isn't widespread, since there are a few reviews on Steam where the game was primarily played on a Steam Deck, and MangoHUD does report that you can get roughly four hours from a full charge, but at the moment, those hoping to play the game while on the go should wait for more patches before taking the plunge.

Ultimately, Calcium Chaos: Derailed is a fine twin-stick shooter. The shooting is fun, while the roguelite elements make things interesting even if the game never fully leans into it. The ability to combine weapons is what makes the game enjoyable, especially when you find a wild combination that goes beyond your expectations. This isn't a particularly difficult title, and there are a few bugbears, but it's a good game for those who want to play something to bide their time between bigger titles.

Score: 7.5/10