The Vortex Hive
The Vortex are an advanced species, able to harvest their food form Earth's water by using some sort of tractor beam or as I like to believe it as a Vortex porthole that leads to a long tube. The Vortex harvest from Earth's sea’s every 500 years, when the planets are in alignment, because it is said that they have lost their own ability to make food. Ecco and his famliy or pod was cought by this, during one of the harvest in the first Ecco the Dolphin, he had then weakened and intrigued the Vortex Queen enough that she followed him back to Earth to start a new hive, in Ecco The Tides of Time. But because Ecco used the time mechine to time travel in the first game, in the second game he had some how split time stream, where there was the Light future and the Vortex Dark future.
The Vortex hives are mechanical, with alien like structures that shoot these organic cell like things, that can hurt their foe, these are believed to be for defense purposes, also in addition a very strong currents of water which is dangerus to non-Vortex life. The hives are mainly underwater, though some parts are above the surface, whether this was done by the Vortex or the result of falling water levels is unclear.
The Vortex have good knowledge in producing electricity and they are known, according to Wikipedia, to possess a powerful weapon capable of destroying entire cities on other planets. It has been romored that Atlantis was destroyed by this weapon. In the dark future, the Vortex had created antigravitational devices.
The Fate of the Vortex:
The Vortex Queen finds the time machine and escapes into the past. When the Queen arrives in the prehistoric era, she encounters creatures she cannot rule. She has no choice but to live within the life cycles of Earth. And, through the eons, the Vortex integrate with the life on Earth.
That’s what was said at the end of tides of time
The Vortex Queen had decided to remain on Earth, she felt the best way to survive is to evolve and adapt to Earths environment, so she gave origin to arthropods. Based on this affirmation, it is likely that the Vortex have many characteristics of the animals of Earth for example, their exoskeletons could be made of chitin.
The Vortex are able to adapt quickly to new environments, evolving into new forms and/or hybridating with local creatures in order to create new lifeforms. It is likely that they are capable of bioengineering to some extent, as well.
The Vortex creatures:
The Vortex Drone in the first Ecco they were a green color and had heads shaped like a Squids, along with thin, skeleton like bodies.
In Ecco Tides of Time the Drones are a light blue color.
Votex Drones MK2
These Drones are like the Vortex Soldiers, they have the same colour as the Drones from the first Ecco but look more different, they were more black and had a skeleton like appearance to them, the look like a machine then anything else.
The first version was had a large exaggerated skull-like head and will attempt to capture Ecco, while the other has a ridged, bladed head similar to the standard Vortex drones and will attack Ecco. These drones are bioengineered on Earth to withstand high water pressures and they will explode if they get too close to the surface.
The Vortex Queen is the mother of all Vortex and the most intelligent among them, she is like the brains of the hive. In the first Ecco she looks like a large, disembodied Vortex Drone head, Where in Ecco The Tides of Time she looks like a huge, red worm with her mouth showing and her claw like tongue is used to pull her prey into her, yummy.
Vortex larva are a clear, shaped like a rounded Jelly Fish with two large tentacles that look like a chain of bubbles.
Vortexs Animals:
There are other creatures that the Vortex has but they look different from the Vortex people, they look like our version of our animals but different, This could be due to the Vortex's bioengineering and hybridizing skills.
Vortex Jellyfish can be found in a few levels in the second game of Ecco, they are from the planet Vortex. They act like Earthling jellyfish but they are a colour brown with black spots and they have one single tentacle at the bottom of their bodies. They are poisonous even for the Vortex themselves.
Amoebas can be found in the Vortex future or on the Vortex home planet, these blob-like creatures are able to travel through water and air. But in the air they are weaken and becoming vulnerable to Ecco's sonar.
Globe Holder is like a huge bio-ball, similar to a stiff, oversized Amoeba held to the floor and ceiling of a room by bio chains, this creature is the one in the dark future that holds two of the Asterites globs. It is believed tp be a biological machine rather than an actual lifeform.
Worms can be found in many places and there are many kinds of worms that could of came from Vortex in the second game. They are like hybrids created on Earth and these are the types you have:
White worms are formed by a line of spheres connected it’s head. These worms have a different behavior, some of them chase Ecco, while others are attached to things from their tails which limits their reach, these ones have thinner bodies. At some point in the game Ecco encounters worms called the Magic Arm. These have fixed heads and attack with their tails. None of these worms are found near the surface and they don't follow Ecco there.
Red worms can be found in the Vortex future or on the planet Vortex, their bodies are thicker and look like red spheres but their head is more different. They can live outside the water and inside the waters.
Brown worms, like the Red worms have brown sphered like bodies and have a sting at the rear side and their heads seem to have no eyes.
The Foe:
Now in Ecco, The Defender of the Future, the Foe were similar to the Vortex, except they look more fish like and had similar looks to our sea creatures of sea’s but looking more alien and very tough armored.
There where different types of Foe, the Shark like Foe that attacked you like the Sharks would, the Snake like Foe that would fire projectiles at you and the only way to kill them is with Sonar burst but sometimes they can’t be killed at all, then there was these Foes that hung on the ceilings and would grab you if you swam under them, and then you have the Foe Queen who is this big Alien looking creator that has control over the Foe hive.
Now little is known about the Foe but my guess is they are like the Vortex but are more like the Wraith from Stargate Atlantis, except they feed of living things by eating them, rather then just sucking the life force out of them.
So my guess is if you watched Stargate Atlantis you might get the story of this game but in a different world.
Credit for information does not go to me ^^