Cademimu was originally a levelling flashpoint accessible to both factions, designed for levels 27-33, and is now accessible to levels 15-65 as a tactical. It's one of those "story-light" flashpoints from launch, alongside others like Hammer Station and Red Reaper, which I already talked about. It didn't have a hardmode version at launch but received one with the release of Rise of the Hutt Cartel.
Cademimu V is a Republic city world similar to Coruscant, distinguished by skyscrapers and high walkways without safety rails. Unlike Coruscant (for all its problems), it's in the grip of an outright rebellion.
You spend the flashpoint fighting separatists, who are mostly humanoid soldiers, though they are also supported by droids and some hounds. Some of the larger pulls can be pretty tough, especially those containing hounds. The larger droids are often near the edge of a platform and can be insta-killed by knocking them to their death (which is a lot of fun).
Of course the lack of safety measures means that players also have to watch out for deaths by falling themselves, and there is an infamous "lift boss" near the end, though it has been nerfed since launch as its speed used to be much more annoying. My fifth post on this blog ever was about encountering this lift boss and being greatly amused by it.
Once upon a time...
Like in the other flashpoints of this "story-light" style, there are a bunch of gathering nodes for various crew skills that allow you to unlock shortcuts or temporary combat pets to assist you.
The boss encounters in Cademimu are all fairly interesting. The first fight is against a corrupt police officer who tries to arrest you with his droid. Traps will be placed on the ground that incapacitate and damage players if they stand in them, but they can also be used to stun the droid if the person he's currently targeting lures him into it. It's interesting to note that this fight can be tackled more than one way: some groups burn down the droid first, others the officer. The important thing is that the players themselves don't get caught in the traps and don't let the droid catch them, as he hits pretty hard.
The second fight is against a Wookiee spacer with a flame thrower and a bunch of Ugnaught mechanics as adds. It's a bit random, but I guess the separatists hired him or something? This fight poses the challenge of dealing with adds that are not too easily killed (as they are all silvers), however with some skill they can be pulled into the boss's flame thrower so that his own ability helps with killing them.
Finally there's General Ortol, the last boss. He's, again, one of the game's more memorable encounters in terms of mechanics, as it takes place underneath a bunch of rockets, and the boss keeps instructing his troops to fire them. If you're underneath a rocket when it ignites, you're toast! I'm pretty sure that nearly everyone who's ever done this flashpoint has died to this mechanic at least once initially (as it's not very obvious just how far the rockets' reach is).
This fight requires an unusual amount of spacial awareness of players, as they need to look up every time Ortol's audio cue warns them to make sure that they are not in a danger zone. The boss also has a knockback, and in hardmode it comes with the added challenge that he occasionally roots people with magnetic shackles. These can be broken with any ability that removes movement impairing effects or by another player running over and touching the shackled character. This requires both situational awareness and teamwork, as people constantly need to free each other to not get trapped underneath a rocket about to fire.
Depending on your faction, either Master Satele or Darth Malgus inform you that there is unrest on the Republic world of Cademimu V. Governor Chornarov has declared independence and martial law - Master Satele assures you that the planet's people do not approve of this but are being oppressed by a bunch of war criminals, as Chornarov has built a private army consisting of former separatists from Ord Mantell. In addition to this, Cademimu is known as the "war chest of the Outer Rim", as it stocks missiles to defend at least three other planets in the region, which makes its sudden secession both dangerous for the Republic and an interesting opportunity for the Empire.
You are supposed to land a small strike team near the planetary missile control centre to deprive the Governor of his power and take over. You spend the entirety of the flashpoint fighting your way to this building, but when you arrive you find that the launch sequence for the main missile battery can't be aborted anymore - you can redirect them however. The light side option is to aim them at an uninhabited moon, while the dark side option lets you target the enemy faction's fleet in orbit.
Once upon a slightly later time...
At the end you face off against General Ortol, the leader of Chornarov's private army and a major war criminal from Ord Mantell. Once you've beaten him and taken control, the flashpoint ends, and you only hear about the aftermath in the debriefing, where you are told that the corrupt governor will be taken care of.
For a flashpoint that doesn't present you with a lot of story in the actual instance itself, Cademimu still has a pretty deep background. It's interesting that you never actually meet the main antagonist, Governor Chornarov - as you make your way through the instance you just keep hearing him make announcements about how everything is peachy while you fight his troops.
Cademimu's lifts and chasms make for an interesting environment that allows you to speed up some encounters by knocking things to their deaths, which is immensely satisfying if you play a class that can do so. At the same time this also offers plenty of opportunity for hilarious player death.
Finally, all the boss encounters are fun and engaging, as they feature interesting twists such as being able to use boss abilities to your advantage and having to pay attention to the third dimension (without requiring any jumping craziness).
For all these reasons combined Cademimu is probably my favourite of this set of six flashpoints from launch - even after running it four times in a row recently I only got mildly tired of it, something I don't think I would have been able to say about many other instances.