Lorenzo, as promised, held an introductory lecture on Cruxi in a classroom of the fortress ship. Standing before a podium, he was surprisingly analog in his teaching methods, utilizing videos and screenshots on a projector instead of holograms like most academic institutions have normalized. He gave reasons for why there is still very little that is known about them even after centuries of warfare: the Cruxi employ communication-hindering technology and catch planets isolated by jumping in through hyperspace, and only in rare cases have victims escaped their relentless invasions. They are also very protective of their secrets, and employ self-destruction mechanisms for both their equipment, and disturbingly, even their own troops. However, in more recent times, humanity has been able to predict their invasion patterns based on collected data. At one point, he held a pop quiz to startle any pilots who may have snoozed during class. He was strict when teaching, and did not tolerate any distractions in his class, which resulted in Griff getting sent to the brig for one too many comments about how boring the class was.

"To begin with," Lorenzo spoke as he continued the lecture after Griff was sent away, "You must understand that there is no single Cruxian species. Rather, the term Cruxi refers to a force of various alien species that seemingly serve in a caste system." He showed a picture.
"For example, this [url=https://imgur.com/9Bf5sg4]servitor species[/url] is among their most numerous, tasked with various labor positions. Based on autopsies that humanity has performed, some of them are cybernetically modified for piloting their various vehicles, including the [url=https://imgur.com/a/xoUJNdn#pUd3AeM]Cruxi War Machines[/url], their main weapons in an invasion."

He showed a video of a wide alien knocking over a car with a shoulder tackle. 
"They also have [url=http://i.imgur.com/hOMKkuw.jpg]front-line shock infantry[/url] equipped with energy shields and plasma rifles, and tasked with assaulting key defensive locations in tandem with an armored assault. Study has revealed their genetic material to be near-identical, which lends credence to the theory that these soldier-types are genetically engineered and mass-produced in cloning facilities."

Then he showed a picture of a rather nasty alien.
"Another type we have recognized are designated as a [url=https://imgur.com/RPrl6rf]hunter-assassin caste[/url] that infiltrate enemy facilities, eliminate key targets and infect the corpses of their victims with their eggs, spawning more of their species behind enemy lines.
Recent reports have mentioned more advanced members of this species even being able to shapeshift and mimic humans, so take caution whenever you spot suspicious behavior, and remember to use rotating pass phrases when encountering one another on the field outside of your Frames."

Finally, he started talking more about the opposition the pilots themselves would fight.

"First of all, they employ various [url=http://i.imgur.com/yD09nVw.jpg]troop ships[/url]. They are a low priority, but if you happen to have the opportunity, shoot them down. However, these won't be your main opponents in the field," Lorenzo said while pointing at a new picture during his lecture.
"While planetary defenses are, by this point, prepared for holding out against an infantry invasion, they struggle against the war machines they utilize, with the Cruxi War Machines, or CWMs for short, previously shown being their main units. They stand about half a regular Framewerk's height, but where they lose in size they more than make up for in their numbers. You can expect to see yourselves outnumbered by these units while out there in the field. While the type I'm showing you is dedicated to fighting at range with a pair of plasma cannons, there have also been documented cases of CWMs equipped with rending claws as well as [url=http://i.imgur.com/6jCfvfR.jpg]building-sized bioweapons[/url] strong enough to immobilize a Framewerk with their tentacles as they bite and claw through armor using acidic spit. Sometimes more advanced models accompany them such as these [url=http://i.imgur.com/sSDa3H9.jpg]long range sniper-type[/url] Cruxi mechs."

He sighed, and then gave a final picture.
"As an aside note, I would like to mention that, despite our attempts, we have yet to capture a member of what we believe to be their [url=http://i.imgur.com/ToXWF9o.jpg]ruling caste[/url]: the following picture has been formed using artificial intelligence based on reports and illustrations scrawled by eyewitnesses on the field, and escaped prisoners of theirs. Therefore, it is possible it may not match the actual appearance for them, so keep an eye out. For the most part they only seem to be located on their battleships that escape into hyperspace at any documented case where their invasion was thwarted, but I know that they must also be present during the later stages of the invasion directing their troops. All in all, while these are the types of Cruxi and their weapons we know about, there may be more unidentified and dangerous weapons currently built by them to counter our use of Framewerks. Be extremely cautious when engaging them. Now then, class is dismissed." Lorenzo then went back to organizing the pile of papers he had with him.