Well, I don't know anything about killing vornians, but maybe some tips on destroying Voinian ships will suffice.
1: Weapons most effective are: Rockets, Emalgha Cannons/"Turrets", space mines (boooooo), hunter missiles (too little damage for my tastes), and neutron weapons
2: Phase weaponry does little damage per shot, but if you have enough cannons or turrets you can do some damage.
3: Here's a real tip: Purchase one or two rocket launchers, make sure you have room for rockets, and go after the Voinians. Since Voinian Heavy Fighters and Interceptors will normally have leftover rockets in them after they are disabled, just go around the battleground boarding those ships and taking the rockets whenever you run out. (This is also a good strategy for the Dreadnought and it's Interceptors)
4: When in doubt, run!. Your shields and armour will almost always recharge faster than any Voinian ship (including the fighters). You can circle around them at a distance and just wait for your shields to recharge, then come back in swinging.
These are just the bits of advice off the top of my head, maybe I'll think of more later.
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One cannot walk down an avenue, converse with a friend, enter a building, browse beneath the sandstone arches of old towns without meeting with an instrument of time.
Time is visible in all places.
Clock towers, wristwatches, church bells divide years into months, months into days, days into hours, hours into seconds, each increment of time marching after the other in perfect succession. And beyond any particular clock, a vast scaffold of time, stretching across the universe, lays down the law of time equally for all.
In this world, a second is a second is a second.
Time moves forward with unwavering regularity.
Time is an infinite ruler.
Time is absolute.