Master of Orion II: Battle at Antares/Physics

The Physics techs appear in the bottom left box in the Research Menu.

The Physics and Force Fields tech tree between them force non-Creatives to make some really difficult choices. The problem is that, if you take the best choice at each individual level of Physics, you get no better beam weapon than the pathetic Laser Cannon until you reach Phasor in the upper half of this tech tree. You could decide to make missiles your main space combat weapons, a perfectly reasonable approach that many players adopt; but this leaves you without a useful PD weapon to deal with enemy missiles and fighters ( Anti-Missile Rockets can't target fighters). There are two solutions, both with down-sides:
 * 1) Take Fusion Beam rather than Fusion Rifle, which means your Marines have to make do with the unimpressive Laser Rifle for a long time.
 * 2) In the first Force Fields tech level, take Mass Driver as your first decent "beam" weapons. You forgo ECM Jammer, and and have to hope either that no opponent ever uses torpedoes or that you get one of the much later jamming techs before enemy torpedoes cause you heavy losses.

0 RP: starting techs
None. You have to research all the Physics techs if the game starts at Pre-Warp.

50 RP: Physics
This is a "general" tech level - even Uncreatives get all the techs. Ship beam weapon that does 1-4 damage, minus whatever is blocked by the target's shields. Not useful until you get all of the modifications; even then Class 3 Shields generally make them ineffective. PD Lasers are particulary ineffective.Miniaturization: Reduces size and cost. Modifications: (0) HV, PD; (1) AP, CO, NR; (2) AF. This large set of modifications is mainly for the benefit of Uncreatives, who might not get a better "beam" weapon for a very long time. Achievement that increases ground units' effectiveness by +5%. Not cumulative with other rifles. Achievement that extends warships' and Star Bases' ability to detect enemy ships. The maximum detection range depends on the enemy ships' size and is 1 parsec + 1 per size class, so it ranges from 2 parsecs for Frigates to 5 for Battleships (and 6 for Titans, 7 for Doom Stars if you don't get better scanners before someone builds these larger ships). The upgrade is immediate and free.
 * Laser Cannon
 * Laser Rifle
 * Space Scanner

150 RP: Fusion Physics
Ship beam weapon that does 2-6 damage, minus whatever is blocked by the target's shields. The lowest-tech beam weapon that's useful, especially with all the modifications; but it has twice the normal rate of dissipation, i.e. reduction in power per combat square between the weapon and its target - that's one reason why Augmented Engines are usually the best choice at the 3rd level of the Power tech tree. Even so, Class 3 Shields generally make them ineffective. In terms of ability to do damage fully-modified PD Fusion Beams are the most powerful PD weapons until Phasors (below); but their twice-the-normal dissipation has the tactical disadvantage that it's difficult for one ship to help defend another that's attacked by a swarm of missiles or fighters.Miniaturization: Reduces size and cost. Modifications: (0) HV, PD; (1) CO; (2) ENV. Achievement that increases ground units' effectiveness by +10%. Not cumulative with other rifles. The best rifle you'll get for a long time.
 * Fusion Beam
 * Fusion Rifle

Best choice for non-Creatives: Fusion Beam, for the reasons given above and despite the fact that you won't get a better rifle before you want to start invading.

250 RP: Tachyon Physics
Achievement that allows you to tell a ship within 3 parsecs of a colony or outpost to change course in mid-transit, and adds 1 Command Point for each Star Base, Battlestation, and Star Fortress. Not cumulative with any other communications Achievement. Achievement that extends warships' and Star Bases' ability to detect enemy ships to 3 parsecs + 1 per size class, so it ranges from 4 parsecs for Frigates to 7 for Battleships (and 8 for Titans, 9 for Doom Stars if you don't get better scanners before someone builds these larger ships). Your Star Bases, Battlestations and Star Fortresses also decrease aggressors' Missile Evasion by -20%. The upgrade is immediate and free. Ship Special System that increases "beam" weapons' chance to hit by +50%, and increases scanning range outside of combat (on the Galaxy map) by 2 parsecs.
 * Tachyon Communications
 * Tachyon Scanner
 * Battle Scanner

Best choice for non-Creatives: Battle Scanner is essential if you intend to use "beam" weapons. Otherwise probably Tachyon Communications, as the next communications tech is 3 levels up.

900 RP: Neutrino Physics
Ship Weapon that does 3-12 damage, minus whatever is blocked by the target's shields; and also kills 1 enemy Marine for every 5 points of damage that penetrate the shields. Neutron Blasters don't have AF or ENV modifications and as a result are less effective in destroying enemy ships than other weapons, however their ability to kill marines can help you defend against enemy boarding ships or make it easier for your own boarding ships. Miniaturization: Reduces size and cost. Modifications: (0) HV but not PD; (1) CO. Achievement that extends warships' and Star Bases' ability to detect enemy ships to 5 parsecs + 1 per size class, so it ranges from 6 parsecs for Frigates to 9 for Battleships (and 10 for Titans, 11 for Doom Stars if you don't get better scanners before someone builds these larger ships). Your Star Bases, Battlestations and Star Fortresses also decrease aggressors' Missile Evasion by -40%. The upgrade is immediate and free.
 * Neutron Blaster
 * Neutron Scanner

Best choice for non-Creatives: Neutron Scanner. The hard decision to take Fusion beam above and make do with Laser Rifle means Neutron Blaster is unnecessary.

1150 RP: Artificial Gravity
Ship Special Weapon that greatly reduces the target's combat speed, and can even immobilize enemy ships, which makes it very easy to hit them (it usually takes 3 to 4 Tractor Beams to immobilize a Battleship - the effects are cumulative). Ship beam weapon that does 3-15 damage, minus whatever is blocked by the target's shields; in addition the target's structure is damaged, even if its armor is still functional, provided the shields are penetrated; when both shields and armor are gone enemy ships evaporate quickly, since now both the normal and "bonus" damage are done to the structure. A good weapon whose main limitation is shortage of modifications.Miniaturization: Reduces size and cost. Modifications: (0) HV but not PD; (1) CO. Building that eliminates gravity penalties on planets whose gravity is outside the colonist's comfort zone.
 * Tractor Beam
 * Graviton Beam
 * Gravity Generator (120 PP; maintenance 2 BC)

Best choice for non-Creatives: Gravity Generator, unless your race is High-G (the penalties for lower gravity are half those for higher gravity than your race is accustomed to) - but even then Gravity Generator would be a good choice, since you will almost certainly conquer some High-G planets inhabited by Normal-G or Low-G races. That means most non-Creatives forgo Graviton Beam, although it's a good weapon.

1500 RP: Subspace Physics
Achievement that allows you to tell a ship within 6 parsecs of a colony or outpost to change course in mid-transit, and adds 2 Command Poinst for each Star Base, Battlestation, and Star Fortress. Not cumulative with any other communications Achievement. Achievement that increases rate of ship travel between your colonies by 3 parsecs per turn.
 * Subspace Communications
 * Jump Gate

Best choice for non-Creatives: Subspace Communications, as non-Creatives usually forgo Tachyon Communications in order to get Battle Scanner.

2000 RP: Multi-Phased Physics
Ship beam weapon that does 5-20 damage, minus whatever is blocked by the target's shields. It's the only researchable weapon that allows the Shield Piercing modification, which makes normal Phasors significantly more effective than Heavy Mount versions(which are normally used in order to overcome the damage block of shields and early game attack range problems) and coupled with High Energy Focus they can completely devastate ships that don't have Hard Shields. Phasors are also the most powerful PD weapons you can research, but until you miniaturize them enough to use their AF modification, it's best to keep using PD AF Mass Drivers or PD CO ENV Fusion beams.Miniaturization: Reduces size and cost. Modifications: (0) HV, PD; (1) CO, SP; (2) AF. Achievement that increases ground units' effectiveness by +20%. Not cumulative with other rifles. Ship Special System that increases the damage shields can absorb by 50% of their maximum strength.
 * Phasors
 * Phasor Rifle
 * Multi-Phased Shields

Best choice for non-Creatives: Phasors, for the SP and PD capabilities. Phasor Rifle becomes obsolete after just one more level of research and the effect of Multi-Phased Shields is not very significant.

3500 RP: Plasma Physics
Ship beam weapon that does 6-30 damage, minus whatever is blocked by the target's shields; and it's naturally enveloping, so when the shields are down it does quadruple damage. Its worst limitation is its twice-the-normal dissipation per combat square between it and the target; but this can be reduced by good combat mobility, which is available very early with Augmented Engines. It's brutally effective against targets with weak or no shields, including Antarans. Miniaturization: Reduces size and cost. Modifications: (0) HV but not PD; (1) CO; (there are no level 2 modifications; it's naturally enveloping). Achievement that increases ground troop combat rating by 30%, the best rifle in the game. Not cumulative with other rifles. Ship Special Weapon that is naturally enveloping and does 5-25 damage per turn, decreasing at a rate of -5 per turn. A very dangerous weapon, but that makes ships that use it priority targets; the best counter to it is to retreat "webbed" ships during combat. That means it's best used with Warp Dissipator. Miniaturization: Reduces size and cost. Modifications: none (it's naturally enveloping).
 * Plasma Cannon
 * Plasma Rifle
 * Plasma Web

Best choice for non-Creatives: Plasma Rifle, because it's the best available rifle.

4500 RP: Multi-Dimensional Physics
Ship beam weapon that does 40 damage, minus whatever is blocked by the target's shields, and with no range dissipation. It's pretty bulky, so Phasors provide a lot more damage per unit of space, until you max out it's miniaturization or face Class X Shields + Hard Shields. It's more expensive than most weapons, so a battleship armed with Disruptors costs about 7% more than one with equally advanced alternative weapons.Miniaturization: Reduces size and cost. Modifications: (0) HV but not PD; (1) none; (2) AF. Orbital building that enables you to launch an attack on the Antarans from the system in which the Portal was built. You can only research this if you selected "Antarans Attack" during game start-up.
 * Disruptor Cannon
 * Dimensional Portal (500 PP; maintenance 2 BC)

Best choice for non-Creatives: Dimensional Portal is essential if you want to attack Antarans (often forbidden in multi-player games). Otherwise you're left with the Disruptor Cannon.

6000 RP: Hyper-Dimensional Physics
Achievement that allows you to tell a ship anywhere on the Galaxy map to change course in mid-transit, and adds 3 Command Points for each Star Base, Battlestation, and Star Fortress. Not cumulative with any other communications upgrades. The upgrade is immediate and free. Ship beam weapon that does 100 damage, minus whatever is blocked by the target's shields, but with double the usual range dissipation; this limitation can be reduced by good combat mobility, which is available very early with Augmented Engines. Does not miss unless the target has a Displacement Device, so is useful for players with poor computers. Very bulky initially.Miniaturization: Reduces size and cost. Modifications: (0) HV but not PD; (1) none; (2) none.
 * Hyperspace Communications
 * Mauler Device

Achievement that extends warships' and Star Bases' ability to detect enemy ships to 7 parsecs + 1 per size class, so it ranges from 8 parsecs for Frigates to 11 for Battleships (and 12 for Titans, 13 for Doom Stars). Sensors also reduce the effectiveness of enemy jammers, reducing their Missile Evasion by 70%. The upgrade is immediate and free.
 * Sensors

Best choice for non-Creatives: depends on the situation. Do your utmost to finish the game before any Creative players get all 3!

15000 RP: Temporal Physics
Ship Special System that enables the ship to move and fire twice per combat turn; the 2nd "mini-turn" is after all enemy ships and bases have fired. Very bulky initially.
 * Time Warp Facilitator
 * Miniaturization: Reduces size and cost

This is both a ship-based and ground-based weapon. Both versions are terrifying: they do 400 damage (what shields?); are naturally enveloping, i.e. do quadruple the stated damage; have no range dissipation and unlimited range; and they do not miss (the Displacement Device does not affect the stellar converter); and the ship-based version completely destroys a planet when used for orbital bombardment, turning it into an Asteroid Belt. The ground-based weapon is even more horrific if protected by good armor and a good planetary shield (Flux Shield or Barrier Shield). But it's not invincible: a pair of extremely good Titans can beat the ground based version, usually without losing one, even if the Stellar Converter is maximally hardened and is the last of 4 ground-based defenses to fall - but only if the attackers are the Warships From Hell, with the right techs from Orion and the full Creative firepower enhancement kit. Of course a larger fleet of smaller ships can do the job, if you have enough Command Points and enough industrial capacity to replace your very heavy losses quickly before taking on your opponent's next Stellar Converter; the "many small ships" approach exploits that fact that the Stellar Converter's enormous power is largely wasted on small ships.
 * Stellar Converter
 * If built on the ground: 1,000 PP
 * Maintenance: 6 BC
 * Modifications: None
 * Miniaturization: Reduces size and cost

Achievement that enables all your ship to move from any colony to any other in 1 turn, regardless of drives and distance. If an enemy with Star Gates gains a colony in one of your systems, either by conquest or by colonization, you will lose that system because the opponent's entire fleet can magically appear there at any time.
 * Star Gate

Best choice for non-Creatives: Depends on the situation. If you are on the offense, the time warp facilitator is the best choice. If you are defending, get the stellar converter or the star gate. Do your utmost to finish the game before any Creative players get all 3!

25000 RP: Hyper-Advanced Physics
The late-game high-tech beam weapons are all in the Physics tech tree, so at least 2 Hyper-Advanced Physics levels will be useful in miniaturizing your weapons. 5 levels of Hyper-Advanced miniaturization enables a Creative player to build a Doom Star with a Time Warp Facilitator, 4 Stellar Converters, a lot of fly-swatters and a Subspace Teleporter (device instantly moves the ship to anywhere on the combat map, in this case to the far edge so it's out of range of most defenders before it starts demolition) and the usual firepower enhancers - this ship is not invincible, but that's another story!