Beam weapons are the mainstays the entire game. Unless you are designing ships to do one specific thing and do it very well, you will probably be using a lot of beam weapons, maybe even then as well.
Beam weapons are the loose category of everything that can be shot every single turn other than equipment specials (assuming the battle is at least 11 turns long).
Missiles and Torpedoes are out because they fail this limitation. Bombs, death weapons, and other weapons like these only have 10 shots.
What are left are things like Lasers, Fusion Beams, Graviton Beams, Auto Blasters, and so on. Only these things are affected by the High Energy Focus, other types of weapons are not. If High Energy Focus can affect it, then it is a beam weapon.
These are the real workhorse weapons and most ship designs should use plenty of them.
Some things to keep in mind when using beam weapons:
- You want to be able to attack first, if possible. Try to use some beam weapons with extra range, such as heavy mounted weapons, or use the High Energy Focus. Also try to move before the other player because then you can fire defensively on their ships as soon as they come into range if you don't shoot them on your own turn. Try to include one of a low level missile on the ship as well. You can turn this off in combat and your ships don't have to end their turns after they fire all their weapons (because they won't fire them all). This will let you move, then shoot, then move again.
- Maneuverability is important to help close in on the enemy ships and planets quickly, subjecting you to their attacks for a shorter time before you can start unloading your main damage.
- Beam weapons do half damage against planets before shields are factored in. Don't plan to use them as your main weapons to damage planets with.
- One weapon shot can only kill one ship. If you want to kill massive numbers of smaller ships quickly, larger numbers of weaker weapons are usually best. Try to use auto-fire weapons when you can, especially the Auto Blaster and Gauss Autocannon because they kill small ships very quickly and "thin out the enemy herd".
- The user of High Energy Focus is the one that dominates space combat. It gets rid of practically all of the disadvantages of beam weapons and makes beam weapons the undisputed best weapons to use in combat. You should only make sure to add some good battle computers to the High Energy Focus ships, because the attack level of beam weapons decreases by 1 for every space of distance to the target beyond the first.