Alien Tech
The aliens who invaded in XCOM: The RPG have many types of technology which exceeds that of earth in 2013. While much of their technology is superior, it was not so far ahead that they were able to shrug aside earths defenders on a whim.
Contents
Propulsion/Locomotion
Without technological assistance aliens are slower than humans, and most are smaller as well. Given their smaller size they tend to use more compact vehicles as well.
Vehicles
The aliens utilize hover vehicles which rarely contact the ground. They move easily over normal terrain, but have speed problems over irregular and broken ground. They are very fast, but lack ramming and towing capacity.
Spacecraft
Alien carriers are huge, over two million ton vessels (relative to terrestrial vessels by size). Their actual displacement is (likely) much higher because of the superdense alloy hulls, but impossible for scientists to estimate.
Carriers
The carriers each can deploy a squadron of 64 fighters and have enough soldiers and raw materials to create multiple base complexes which cover more than 100 acres. They are armed with 4 batteries of 4 direct fire beam weapons. Their hulls proved virtually impregnable to anything except nuclear armaments, and were sturdy against those as well.
Fighters
Alien fighters perform well in atmosphere, but are not optimized for terrestrial conditions. They have excellent straight-line speed, but lack the maneuverability of the best fighter jets. Their weapons are direct fire beams in 2 batteries of 2. Their hulls are armored similar to a modern heavy tank.
Hover Transports
The standard hover transport carries two squads of 8 Type II Warrior aliens or one squad and 2 battlesuits. They are capable of moving near 100 MPH over clear ground, and maneuvering at 50 MPH. Their hulls are able to withstand multiple direct hits from 120mm cannons.
Cycles
Another common type of transportation utilized by the aliens is the single passenger cycle. They are capable of speeds exceeding 250 MPH and are highly maneuverable at 100 MPH. They are durable, but susceptible to common heavier weapons.
Armor
Alien armor is light and durable. Personal armor is composite, like modern armor, with flexible fibers and rigid plates. The fibers are not much stronger than kevlar, but the plates are at least 75% stronger than steel and composed at least partially with extra-terrestrial alloys.
The battlesuits are made with a denser alloy which has not been chemically identified as yet. They have penetration resistance near a medium to heavy tank.
Weaponry
Aliens utilize two types of personal weaponry. Soldiers carry high velocity, rapid repeating, medium caliber projectile rifles and handguns. Their heavy weapons are direct fire beams similar to those used on the fighters.
Power
The primary means of powering crafts of all type is fusion. The smallest fusion generator in use by the aliens is around 60 pounds. The largest is many tons, powering the large space ships.