Crysis offers quite a few weapons for players to use, as first-person shooters normally do. However, Crysis is a bit different in the sense that the weapons are highly customisable, thanks to the different weapon attachments that you can find and unlock for use. They can be switched in and out at will once they've been found. Each weapon might be limited in the attachments they may equip though.
When it comes to the enemies, you'll come across several different types. They range from human foot soldiers to vehicles and there are also alien enemies. You'll want to be careful about how you engage the enemies as well, because a wrong move could have quite a few of them converging on you at once, though this mainly applies to human enemies thanks to the alarms and such that they can set off.
As mentioned above, weapon attachments are found by picking weapons up in the field that have them and when they've been found, you can use them whenever you want to.
Silencer: The silencer is great for when you want to take enemies out without a lot of noise, though you should keep in mind that it reduces the damage done.
Laser Pointer: The laser pointer only comes in handy when you're firing from the hip, so it may or may not be helpful depending on your play style.
Flashlight: There's not much to say about this. Use it if you don't want to use nightvision and if you don't mind being easily detected by enemies.
Grenade Launcher: It's quite useful, especially when the enemies are grouped and you want to try and take them out all at once.
Tactical Attachment: This is useful if you prefer the stealthy approach, as it allows you to temporarily knock enemies out.
Iron Sight: The Iron Sight is not a good option to use when you have scopes available.
Reflex Sight: This is a great attachment, as it easily lets you see where you're aiming.
Assault Scope: This scope helps you deal with enemies at a larger range, but it's not as good as the Reflex Sight in my view.
Sniper Scope: The Sniper Scope is great for long range combat and it helps make the Precision Rifle seem less useful, due to this scope being equippable on assault rifles.
Scar: This is a really nice weapon, especially when compared to the FY71. But it isn't as useful as it could be thanks to the fact that ammo for it is quite scarce. So, you'll probably want to use the FY71 instead, despite the SCAR being the better weapon. Also, as with the FY71 and the SMG, the SCAR has a wide selection of attachments available for it.
FY71: This is not as good as the SCAR weapon, but you will use this in place of it for much of the game's duration, thanks to the weapon's ammo being plentiful. As mentioned above, it also has a wide range of attachments.
Shotgun: The shotgun is a weapon I didn't use much until the last few levels of the game. The weapon itself does have a few attachments availiable for it, with those being things such as a flashlight and scopes. It mainly comes in handy when dealing with the alien enemies in the water and on foot.
SMG: The SMG is one weapon that you'll want to make you use a scope attachment with, as I found it to be quite inaccurate. Ideally, I'd probably recommend using the FY71 over it if you have a choice and the ammo.
Precision Rifle: Again, this is another weapon I didn't find much use for. The fact that you can attach scopes to the SCAR and FY71 makes it less useful than it could be.
Gauss Rifle: This weapon is useful for taking out any enemy vehicles, especially when you don't have a missile launcher. Granted, it takes quite a few shots to destroy something like a tank.
Minigun: This is a great weapon, though it's only found towards the end of the game. It's useful against the alien enemies, plus the KPA Nanosuit soldiers.
Alien MOAC: This is the weapon you'll be wanting to use for the last few levels of the game when you have the option to, as it can take the enemies out easily enough and it also has infinite ammo.
Missile Launcher: You'll want to keep this loaded with ammo for when you encounter enemy tanks and helicopters, as it's really the one weapon that you have that's very effective at taking them down when you encounter them.
Explosive Charge: These I only used to destroy enemy vehicles, so save them for those occasions, though they can be planted on the floor etc. and detonated that way. Also, it's probably best saving them for stationary targets.
TAC Cannon: You only get to use this weapon once and that is against the end boss. You can also only use it at select points, when prompted by your allies. So, there's not much to say about this weapon, other than it's necessary to use it in the final part of the game.
The Pistol: It's your default side-arm that you'll have throughout the game, though you shouldn't have to use it at all really. It doesn't have many attachments either but a bonus is that you can wield two pistols at once.
KPA Soldiers: The KPA soldiers come in several varieties. They're your basic enemies throughout the game and it's worthwhile killing them whenever possible for the ammo and weapons they carry. There's your normal grunt, who are easy to take out, then there are the elite soldiers. You'll be able to recognise the elite soldiers because they carry better weaponry than the standard enemies.
Also, there are often at least two KPA soldiers in cars, when they're encountered. If you take out the gunner, the driver is likely to get out. The cars themselves are not much of a danger though if you can take out the gunner and if you leave them intact, they can be driven.
They'll also sound alarms when possible so take them out silently whenever you can.
Tanks and AA Guns: Tanks will trouble you throughout the game. While you can use the Gauss Rifle to take them out, which takes a lot of shots, it's best to use the missile launcher on them. It's also best to avoid using the Explosive Charges on them as you need to get close enough to use them. So, save your missile launcher ammo for them.
Regarding AA Guns, they're not really a threat. They're what you want to save your Explosive Charges for.
KPA Nanosuit Soldiers: You'll encounter these soldiers for the first time at the end of the third level. They're tough and they can cloak, so make sure you're paying attention to your surroundings when facing them. In addition, you'll need to keep up sustained fire on them to bring them down. Towards the end of the game as well, they'll be equipped with Miniguns.
Aliens: The alien enemies come in several varieties. The first time you encounter them, when you can actually kill them, they'll be in the water and will either attack you via melee or with guns. In either case, you'll want to use the shotgun on them for easy kills, though an assault rifle also works.
Outside of the ones encountered in the water, you'll face large flyers and some smaller enemies who are dropped by the large flyers at times. The small ones tend to be quite numerous and they use a weapon that's similar to a machine gun, in terms of fire rate. Until you get the MOAC gun, you'll want to use the shotgun to bring them down. The MOAC gun also works for the large flyers. The Minigun also works for either of the two alien types.
When it comes to a big walker enemy that is alien in origin, don't bother fighting it until you're on the ship. You can't kill it until the ship part.
- All references and screenshots from Crysis.