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******** SERIOUSLY?!!...jeez this was discussed over so many times..look guys, im tired of stating all real facts on them but ok..Starcraft Universe pwns Halo's Universe hands down, by technology, power, and form. your trying to make out UNSC weaponry thats just like our present rifles, towards a gauss rifle that shoots .50 auto hypersonic uranium spiked bullets? I dont think so. Also, they just scratch Zerg carapace, making out that UNSC weaponry on infaantry and most vehicles are otherwise useless on even the weakest Zerg, the Zergling, in fact, in a fan dispute, fact to fact, power to power, a Hydralisk is able to stand toe-to-toe with Master Chief, and actually win without even getting a scratch (Zergs are born to be already powerful killers, and flexible like assassins..) all UNSC weaponry will do nothing but piss off the hydra, making the Zerg burrow before suddenly ripping out a scythe claw into Chiefs back and dragging him into the earth, ripping him apart (his shielding also never worked in the factor, signaling that the hydras needles spines and scythe are too powerful for it..i will discuss more tomorrow morning..(btw thecovenant also had the same results..will explain later..)

Im back and yes I do have the facts for both universes, but I'll start in Starcrafts universe in favor, and beginning with the Terrans..:
-Their basic trooper, the Marine, is most likely a murderous killer resocialized, making him far more dangerous then any soldier, meaning he will rush into combat, no ifs and buts, gauss rifle blazing with powerful accuracy, and his morale invincible to faltering. He is also equipped with a CMC power armor suit, which provides a special shiedling to Chemical, Radiation, and Environmental damage or changes, the suit is also physically well made, making the Marine a bit bulky is the price for the speed like a Spartan, strong enough to bend metal and punch through walls, take several hits from grenades and shrapnel, and finally well made for MORE customizations.And with the addition on Stimpacks, the Marine is a powerful killing machine..take note that Terrans basic trooper is more powerful then a UNSC spartan, probably faster and more agile because of Stimmies and the Suit, and yet they are killed by the thousands by mere Zerglings or powerful Hydras..
-The maurader, a heavy demo man, his punisher Grenades bring judgement towards any being, his thick powerful armored suit, more bulkier then a Marines, yes the joint placements are just perfect for easy movement, the Maurader too, is a dangerous foe, and could single handedly wipe out a small force of UNSC vehicles using Stimpacks to dodge a Scorpions fire (or take it, after all the maurader's armor can take a blast from a Siege Tanks 120mm Arclite shock cannon) leap up on the Tank, and blow it all to hell..his only one real weakness is mass small units and Air strikes, which zerglings take in delight of destroying them, so possibly a Flood Swarm will prove more then a match for the Maurader, also note that if Hornets are out of reach of the Mauraders grenades, they too can pelter him down, but dont expect the Maurader to be alone, for he is only support, if the UNSC sees a MMM ball rolling in, their entire platoons will be wiped out, possibly their entire army will be, sadly....
-The Reaper, a fast, highly dangerous raider. He is made from one of the worst criminals in society, his jetpacks are made to literally 'jump' over large cliffs and gaps to attack the opposing base, while his pistols can pierce skin and bone, heavily armored beings will be quite a threat to him, however, if he flies with a 'pack' of Reapers, the whole gang is a large threat to the enemy, and should be taken note to be wiped out, since their C-5 Charges are able to destroy any buildings in sight, they truly are ruthless..
-The Ghost, last, but certainly not the least, infantry in the Terrans fold, teh Ghost is truly a nightmare, he is smarter, more powerful, quicker, and deadlier then a Spartan, capable of cloaking, sniping, EMPing a Spartans armor, energy weapons into uselessness, and finally bringing down the thunder with a tactical Nuclear strike in just 20 seconds or less, a Ghost is a all-time threat, and not only is he a threat at long range, killing Spartans and troopers repeatedly sniping them quickly with high precision, he is also deadly in melee range, making him the worst person to face by the Terrans. He is able to out think the other enemy simply by reading the others mind and intel, Ghosts are psi-op troopers, having psionic powers to literally disguise themselves, cloak, and even kill others with their own mind, some say Ghosts even go insane in a killing frenzy when reading too many minds of the corrupted, turning into powerful Spectres and further enhancing their already deadly power...
note: more will be added later..

dont forget teh velocity comrade XD, the C-14 Impaler Gauss rifle's hypersonic bullet is actually strong enough to punch through or smash diamonds, when calculating the power on the rifle, the pure force behind each bullet is like that or stronger then a .50 caliber Barret

and now onward to vehicles!

-The fast Hellion, the new addition in the army, is a fast speeding vehicle with a battle cannon flamethrower on the top mount, enabling it to shoot out a long powerful stream of plasma like fire, cooking men in their armor (so marines and spartans are both affected by this, and no, i will not count the UNSC marines, since they have no armor, power, or anything against a Marine..)

- ahh, the famous Siege Tank, enabled to alter their tank hull into a siege mode artillery battery in just 4 seconds, their truly a threat to all living things. Their 120mm Arclite shock cannon unleases a powerful plasma-nuclear burst, thundering down and creating craters and fireballs miles and miles away (unlike the Wraiths, who fire more closely and their projectiles are slow, the Siege Tank fires a SMART round that basically hits its target almost instantly, causing horrendous damage and destruction) the usual combo in the army is to send the infantry out while the Tanks take position and obliterate the entire enemy forces within a flash...and the sound of Thunder coming down on them.

-last but not the least in the ground vehicles, is the mighty Thor. Standing up to 60 ft tall, possibly 40-60 ft wide, this mech is able to withstand a nuclear blast while blasting others with his Particle Accelerator "Hammers", basically killing any single target until theres nothing but ashes, they can also unleash their 500mm cannons on their backs, wiping out anything in frotn of them. Thors are designed to be doom-weapons, going in on the front and wiping out enemy defenses and walls and threats for the army, while the men push in, the Thors are truly a threat to behold.