Guest Star Party Member: In Episode 4, he's kind of busy doing his own thing and jumps in and out of the group when it suits him.
Omnicidal Maniac: No, you're not reading that wrong. The Brahe clan is actively trying to end existence. Tycho, however, differs from his clan in that he wants to make a new world from the ruins of the last.
What the Hell, Hero?: Moira is incredibly horrified when she finds out that Tycho sealed Anne-Claire in the periphery and plans to shoot him. Yog Modiagh's arrival in the Periphery is the only thing that stops her. Though Tycho was fine with being shot as long as their job was done first.
The fists of the Startling Developments Detective Agency. Well-meaning but none too bright, he joined up with Tycho after winning a fistfight with Satan.
Badass Cape: Played for laughs. He dons one resembling Doctor Blood's cape towards the end of Episode 3 and it's anything but badass. It's also been linked to spontaneous internal human combustion. And by "linked to" we mean "directly responsible for."
The Chosen One: In the RPG universe the party enters in ''Episode 3', to everyone's annoyance.
Demonic Possession: He's host to Lucifer, a fact Tycho uses to occasionally mess with his memories.
The ending of episode 4 reveals that Gabe isn't possessed by Lucifer, he is Lucifer, handed down through the Brahe clan as a bodyguard and general thing-puncher. Tycho is apparently the first Brahe who regarded him as an actual friend.
The player character in episodes 1 and 2, who joins the Startling Developments Investigations after his house is destroyed by Fruit Fucker Prime. He's absent from the rest of the series. As explained in the third episode's "Begining of the End" prequel DLC Tycho sealed him in the Periphery and wiped Gabe's memory of him.
Butt Monkey: House gets stomped on by a giant robot, roped into fighting Elder Gods, temporary home gets destroyed, you finally find a new place to stay... gets burnt too the ground. And then see Sealed Badass in a Can below.
Dummied Out / Secret A.I. Moves: Hard to say which this counts as, but if you fight every battle in the third game's extra chapter, beating its final boss gains them just enough EXP to reach level 17, which gives them a move called Rake Armageddon. Too bad the episode ends at that point and there's no way to actually use it in battle. Considering the implications about Rake Guy's nature and abilities listed below, maybe it's for the better.
Eldritch Abomination: A comment in the Episode 3 prequel hints that there is more to you then meets the eye.
Featureless Protagonist: Parodied in Episode 3: since his or her appearance was customizeable in the first 2 games, the short extra chapter in the 3rd episode involving them solves this problem by having Gabe and Tycho randomly decide to refer to everyone with gender-neutral pronouns, with the latter stuffing them in a sack for the entirety of the episode so that nobody can tell what they actually look like.
More Dakka: Rains missiles down from a blimp in episode 2.
Out of Focus: Disappears after the first act of Episode 3 to spend time with her parents. This turns out to be a lie: Tycho instead sealed her in the Periphery so that she could recreate the universe into a far better one after it's inevitable collapse.
A skull in a jar that was once Gabe and Tycho's partner. He's their head of security in episodes 1 and 2 and thus serves as a prop. He joins them in field work in Episode 3 and regains his voice (if not his skin) in Episode 4.
Ascended Extra: Becomes a playable character in Episode 3 and 4 after being a prop in the first two episodes.
A mysterious doctor who helps Gabe, Tycho and the Player in the second episode He's revealed to be serving Yog Modaigh in Episode 3 and steals the paintings it needs to enter this plane. He joins the party in Episode 4, revealing that he was doing so to save his lover Hestia.
Magitek: All the Fruit Fuckers are powered by Dark Steam, making them a blend of science and magic.
No Cure for Evil: Averted. Every few turns, his "Self Repair" skill restores him to full health and heals any status effects or debuffs.
Not so Above It All: Although his main goal, like the other gods, is to destroy the world, the fact that he is possessing Fruit Fucker Prime means he's just as susceptible to oranges as the lesser Fruit Fuckers.
Puzzle Boss: Defeating him requires you to constantly debuff his speed and buffing your own attack so you're able to defeat him before he can use his Self Repair skill.
Yog Modaigh, God of Doors
Don't let the title fool you, Yog Modaigh is no pushover. Rather than simply doors, his domain includes anything that can be considered a passageway, including death.
Fan Nickname: Because his name isn't provided in the game itself, he is commonly called "Yog Baomun" because of a snippet of narration in Episode 1. The Episode 3 prose indicates that this phrase is a salutation.
Genre Savvy: At least enough to know that you don't try to directly fight heroes yourself.
Reality Warper: To a limited extent. He can only control events if they make some degree of narrative sense. Summoning giant monsters with the justification that Tycho and co. hadn't seen them yet is fine. Going "and then the good guys' heads all exploded" is not fine.
The Omniscient: Certainly believes itself to be this. In fact, it's the reason behind his masterminding of the gods' deaths - he's so sick of the constant noise from everyone else's presence that he wants to be the only remaining thing in existence.
Villains Out Shopping: If his dialogue in episode 1 is anything to go by, he has a soft spot for windsurfing. How he does it when he's the size of a continent, we'll never know.
Word of God: The Fourth God's name is unmentioned in the game. Jerry Holkins provided the name at a Q&A panel at PAX Prime 2013.
Worf Had The Flu: After severing the pillars supporting Overhell, Yog Ur keeps it afloat through his power. But doing this takes a lot out of him, rendering him significantly more killable than he otherwise would be.
Not a god per se, but a Tome of Eldritch Lore that exists to do their bidding - and does a damned good job of it, too. Appearing as a gold-plated tome with Penny Arcade's classic wombat logo on the front, the Necrowombicon keeps popping up to cause trouble for our heroes.
Artifact of Doom: In a world filled with artifacts of varying levels of doom-ness, the Necrowombicon is the doomiest of them all.
Book Of Shadows: Its pages can show whatever needs to be shown to further its plans. Tellingly, it stays completely blank whenever Tycho tries to read it (Gabe probably doesn't bother).
Break Them by Talking: Yes, an inanimate object did this. At the end of episode 4, it revealed itself to have taken the form of Tycho's sword, and taunted him with images of the many ways Anne-Claire would die at the hands of Yog Ur. After spending the entire game being subtetly drained by the Necrowombicon's power, plus the despair this display gave him, allowed the fourth God to possess Tycho.
The Corrupter: For a mostly inanimate object, it's very good at enslaving people to do the Four Gods' bidding, including Dr. Blood and Tycho himself.
The Dragon: Effectively acts as this for each of the Four Gods.
Shape Shifter: Disguises itself as Tycho's sword for the entirety of Episode 4.