The Brute (pictured on the right) is a massive golem that looks like that is made out from cooled lava, his loud footsteps are your indicators that it is near, oh and it's also the fastest among the monsters despite its large size.
The Hunter is a translucent slimy creature that has long arms with talons that tends to ambush you.
Last but not least is The Fiend, which is the toughest of all three because of its demonic appearance and its ability to levitate and possessing telekinetic powers, the way it kills you, however, is more gruesome than the other monsters.
One specific death from the Fiend involves him crushing your heart using his telekinesis.
If the Fiend catches the Player Character from behind, he uses his telekinesis to make the PC's head turn 180 degrees.
Special mention goes to the Fiend's life-raft ending, which has it giving a close Nightmare Face while the screen flashes.
The situation that you are in, being stuck in an abandoned large ship, alone, unarmed with a monstrous abomination capable of killing you is anyone's worst nightmare, especially people's suffering from claustrophobia. It doesn't help that the layout of the ship is very confusing and it's very easy to go in circles all the time.
You only face down one monster in a given playthrough, but the notes and audio logs make it clear that all three of them were out and about at one point. The Brute frying an engineer and melting a hole in the engine, the Fiend is causing glitches everywhere, the Hunter exits the vents to get at the ship's food. Two of them are implied by the notes to be former crewmates being treated for burns. So first off, how did the third one get on the ship? Second, where the hell are the two monsters, you don't face? They're not on board anymore. What if they disembarked while the ship was at port in Hong Kong and are loose in the city or commandeered lifeboats of their own and attacked other ships? Best case scenario is that they fought each other instead and you're stuck with the one that survived.
That, or they landed in Hong Kong and the Royal Hong Kong Police Force and/or the Royal Hong Kong Regiment dealt with them. After all, just because a guy armed with, at best, a fire extinguisher can't harm them, that doesn't mean people with actual weapons can't harm them. Even more likely because, while you can't permanently harm them, you can still stun them by spraying a fire extinguisher in their face.
