I'm of the belief that there's no such thing as a best weapon. However, there is such a thing as a best weapon based on category.
You might want to evaluate weapons by:
- Firing speed
- Accuracy
- Raw stopping power
- Weapon weight
- Ammunition capacity
- Price (elerium, alloys, $$$)
- Availability (how easy it is to obtain)
- Etc.
Here are the top 3 weapons by the accuracy and firing speed categories (also divided into their respective firing modes).
Best Accuracy
Launch
1. Blaster Launcher (based on your waypoint plotting skill)
(Only one in its category, since, well, it's special.

)
Aimed
1. Rocket Launcher (115%)
2. Rifle, Heavy Plasma, Small Launcher (all tied at 110%)
3. Plasma rifle (100%)
Snap
1. Plasma Rifle (86%)
2. Heavy Plasma (75%)
3. Small Launcher, Plasma Pistol, Laser Rifle (tied at 65%)
Auto
1. Plasma Rifle (55%)
2. Heavy Plasma, Plasma Pistol (Tied at 50%)
3. Laser Rifle (46%)
Fastest
Aimed
1. Pistol (30%)
2. Laser Pistol (35%)
3. Laser Rifle (50%)
Snap
1. Pistol (18%)
2. Laser Pistol (20%)
3. Laser Rifle (25%)
Auto
1. Laser Pistol (25%)
2. Plasma Pistol(30%)
3. Laser Rifle (34%)
The best damage based on the damage type will always be the biggest gun in any particular series of weapons. Of course, some damage types may prove to be far more effective against certain aliens than others.
For example: Lasers generally do double their standard damage to sectopods, and Chryssalids receive only half the normal damage from high explosives. Stun bombs (and other explosive type weaponry) are extra effective against large terror units on account of them occupying 4 tiles, etc.
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In the end, I feel all it really boils down to is using the right weapon for the right task.
All things considered though, the best balance of speed, firepower, accuracy, etc, must go to both the laser rifle and the heavy plasma. They are, of course, the de-facto all-round most favoured of weapons. I bow to their general superiority.
- NKF
(Yeah, yeah, I'm a bit weird. I've got some of the weapon stats listed on an Excel sheet simply for comparison purposes

)
NKF - finally built a gaming PC in 2020 (though not any of that RGB nonsense). Can now play games up to '89!