The harpoon launcher is your greatest ally in the defense against sharks. When underwater keep an eye out. The bigger the shark, the more harpoons will be required.

You can obtain a harpoon launcher from the buy shacks. Nautikins will start with a harpoon launcher in their inventory in sandbox mode when launching from the dry dock. You can activate the harpoon by equipping it from your inventory and then using interaction-mode and left-click.

The deck gun is a low fire rate machine gun like deck mounted part. It can only be used when a Nautikin is seated and controlling the part. All weapons that are controlled by Nautikins that are a sub part of a vessel are known as "subvessels". Subvessels can be controlled from the map.

This part is good for taking out sharks, light armored boats and anti-air. The impact on another vessel will depend heavily on what it is made out of (i.e. wood vs steel). You can fire the weapon when the aimer is present on screen with left-click. You can change the view with "V" (see controls)

The deck cannon fires H.E. rounds (they explode on impact). It has a much slower fire rate and is primarily useful for taking out ships with heavy armor or generally as artillery. It is not particularly good as anti-air. Extremely dangerous, do not fire near Nautikins.

Some weapons have fixed version of the part that allow you to attach a weapon in a fixed orientation. This is useful for fighter planes or patrol boats. Depending on the orientation of the weapon you will see an aimer on your HUD, if visible (looking in the direction of the weapon) you will be able to fire with left-click (assuming you have fuel). This means that you can have forward and rear weapons mounted and fire independently based on your camera direction.

The missile launcher part functions similar to other deck weapons. Missiles can lock on by holding down the aux fire button (right-click by default). Once a missile is locked on, it will fire when the fire button is pressed regardless of the direction the camera is facing and any subsequent launches while the target is still locked will fire missiles at the same target. Missiles will fire in a prioritized order based on the direction to the target, if you have missiles facing towards and away from the target, the missiles facing towards the target will fire first. Reloading missiles requires a significant amount of fuel so they are not ideal for small vessels. There is also a fixed version of this part that will also lock onto targets.

Firing a missile in multiplayer with target lock will trigger a missile lock alarm on the target vessel regardless of the vessel type. Players will be notified when a missile has been fired, not when the lock occurs.

The missile launcher has a somewhat obvious need for countermeasures so there is another part that allows you to counter incoming missiles.

Countermeasures do not work like other fixed weapons and will fire regardless of the direction the camera is facing and are always ready to fire unless you have toggled them off. The effectiveness of your countermeasure will depend heavily on when they are deployed and the angle at which they are attached to the vessel. Ideally they should be fired after the target lock alarm goes off and before the missile impacts your vessel at an angle that fires the burst of flares away from your vessel. Flares can decoy multiple missiles but do not guarantee success simply by firing them wildly.

Torpedoes work very similarly to missiles in terms of firing and lock on. There are a few key differences.

• Torpedoes will only activate and move underwater.
  
• Lock on requires a shorter range sonar lock.
  
• Sonar lock will not work if the vessels engine is off and moving slowly.

Torpedoes can also be used as inaccurate bombs and will detonate on impact. They can be fire from a submarine or deployed with a slow moving aircraft. Dropping a torpedo at high speeds will likely result in a miss or some sort of undesired explosion. There is no deck mounted version of the torpedo part, however you can build one using the deck controls part.

Torpedoes can be countered by deploying an underwater version of countermeasures, in a very similar way to flare countermeasures (which do not work underwater). They buzz and make a lot of noise in the water to decoy an incoming torpedo. Ideally the countermeasure should be deployed early enough for your vessel to move away from the incoming torpedo to prevent a proximity detonation that could damage the vessel or it's driver.

Underwater countermeasures can also be used as a less effective countermeasure to missiles in the air because they will also confuse the missiles target lock.

This is a very versatile and non-specific part. It has seat controls identical to what you would expect from a deck weapon, however there is nothing attached to it. You may attach whatever you want to it and it will automatically be linked to the movement root of the part, which in this case is the pivot that allows the controls to turn and rotate up and down.

What the heck does that mean?

It means you can slap a fixed gun or missiles on it and build whatever weapon combo you want within the rules of existing parts. This can be extremely useful if you combine it with the camera part which allows you to create a custom perspective. Any lights, smoke emitters, or similar vessel controlled parts will also be linked to the controls (the subvessel).

In this image I have created a weapon using the fixed gun and a camera. It has a smoke emitter and light on it which are controlled by the seated Nautikin and not the main vessel.

Here I have a hastily constructed deck torpedo launcher which can fire 3 torpedoes.

One key limitation to this is that subvessels are intended to not affect the main vessel in terms of collisions and thus existing weapons are designed to not be rotated into the vessel when aiming up and down. The game will allow you to build things that can collide with the boat but will do nothing other than maybe look incorrect if you built a giant structure on it.

A neat side effect of the deck controls behavior is that it applies to all subvessels, meaning that existing deck weapons or cranes for example can be added onto simply by placing parts on them. Any parts placed on a crane will be controllable while in a crane, assuming that the design is functional.

Here is a crane with missiles attached.

There are a bundle of other weapons planned. This guide will be updated as they are added.