Alex trying to flush the plasma weapon he ate down a toilet, only to get confused when it clogs. He keeps pumping the handle until it breaks, sending water everywhere. Cue Alex leaping to the ceiling like an angry, hissing cat.
"She had a sudden mental image of Alex Mercer sitting in a wooden crate, scowling like some avatar of scowliness, and saved that thought for later."
Arcade learning that Alex was the one who ripped down the Followers' gate.
Arcade: Wait, that was you a few days ago? The gate was torn to pieces! Alex:No. It didn't sound convincing even to him.
Arcade in general, really, when playing off Cain and Alex's antics.
Arcade: I am about to die. Cain: Hey, look at it this way. If you die, we're going to die too, so it's not like you got off worse or anything. Alex: I probably won't. Cain: Alex, shh. We're supposed to be a team. Arcade: You're insane. Both of you. Did it occur to you that you're going to light this place up like a bonfire while we're still inside of it?
When the group reports to Hildern that he won't be getting his data, as they thoroughly incinerated the inside of the vault to clear out an infestation of plant zombies, he unsurprisingly isn't happy. When he starts berating Cain for her actions, she points out that it was actually Alex who did the destroying. Hildern looks over at him to deliver a scathing diatribe, immediately notices that Alex is ready to violently murder him if he says one wrong word, and quickly shifts his attention back to Cain.
Alex's Fish out of Water status, when it isn't sad, often leads to moments like this, like wondering why people are so hell-bent on collecting bottlecaps or why anyone would be afraid of a golf club.
Cain's reaction to learning that Alex's clothes are part of his biomass.
Cain: So, what you're saying is, you've actually been walking around naked this whole time.
Then she starts thinking about other clothes he could shapeshift into that would make him look a little less scary. "Maybe a nice muted brown? Or something blue. Blue would bring out your eyes." Alex's reaction is to roll those eyes.
And later, when seeing that He Cleans Up Nicely, she comments that it's a good look.
Cain: Like, you normally look like you hate everything, but this is a little better. Alex: Believe me when I say I hate everything just as much as I did a minute ago. Cain: I never would have pegged you for wavy hair. Kind of curly, actually. You ever think of doing something with it? Alex: Actually, I changed my mind. I hate everything more.
After days of hard work, danger, and running all over Freeside to collect 2000 bottlecaps to get into the Strip, Cain learns that Ralph sells visas into the Strip for only 500. It actually strikes her speechless with how much time she wasted.
Cain learns about Mr. House's sexbots.
Okay. Don't judge, Cain. Lots of people like weird...things. A bit more than regular people do. Or should. And if this guy's as old as I think he is, he probably wouldn't be able to get some any other way and ah fuck how am I supposed to look at him now.
Alex's determination to never let Cain live down how she screwed up while confronting Benny. Cue him frequently bringing up how it would never have happened if he'd been there, and her exasperated responses that she knows, can he just let it go already?!
Caesar's joke about having the Player Character killed can be a tense moment in the game. Here, it's Black Comedy of the highest order, because Alex Mercer is standing right next to Cain and could easily kill everyone in the room without moving from where he's standing. Caesar and his mooks had no idea how close they came to death.
Arcade and Alex. Playing pool. It's a touch surreal and more than a little awkward as the two try to make amends and talk while playing pool. Double points for when Arcade startles Alex, who shoots the cue ball into the wall of the room, breaks the table, and snaps his cue in half, all in one accidental motion.
While infiltrating the White Glove Society, Alex gives Cain a Jump Scare by spending a fair amount of time shapeshifted, then returning to his usual appearance while her back is turned.
Arcade: Were we all...hugging? Alex: Yes. Don't ever do that again.
Cain's Flat "What" when she walks back into the King's School to find Alex in the middle of a Neck Lift interrogation of Pacer, when she had specifically told him to be subtle.
Alex constantly finds new ways to upset Arcade's scientific knowledge. Trying to work out how Alex can run a hundred and twenty miles per hour visibly breaks his mind, and upon seeing him running straight up a wall, Arcade can only whimper "b-but...physics."
Meeting God makes Cain think that Alex is practically a gentleman in comparison.
Cain is not amused to learn the meaning behind her current name, which she picked out entirely because it sounded cool.
Cain: Wait...oh, come the fuck on. You mean I've been introducing myself as Murderface McFractricide to everyone I meet? Alex: Yeah, I guess. He'd thought it was kind of funny.
Alex tries to eat one of the Ghost People. The result is pure Nightmare Fuel, but afterwards he starts kicking himself for being stupid enough to try, despite knowing the Ghost People had bright green blood and "precisely nothing with that color had meant anything good for him, by the Mojave's standards." A few moments later he says it felt like consuming explosives, and yes he has personal experience, thinking "At least those had only gone off once."
With the heist into the Madre ready to get underway, Elijah orders the group to split up and do their jobs, with Alex's being that he has to bodyguard them. Cain points out the little problem that Alex can't be in four places at once. "At least, she didn't think so. He might surprise her."
It's also pretty funny that, for such a Control Freak, Elijah overlooked that little detail. There's even a Beat before he clumsily tries to save face.
Dean Domino tries to buy off Alex. It goes about as well as you'd expect.
Dean: Straight to the point, eh? I like that in a partner. I'm thinking...a contract, you could say. A little protection detail, a change of handlers. Oh, you can still do lookout for your eye candy, I'm not interested in her – but when it comes down to the wire, let money do the talking, yeah? Alex: Fuck off. Dean:What did you say?
When Alex tells Cain about the above moment, he adds that Dean is still around, if she wants to shoot him. For a moment she's absolutely stumped whether he's being serious or actually trying to crack a joke.
Following that, Cain takes a dip into Black Humor herself:
"I can tell. Since, y'know. Head intact."
Cain muses that putting the Super Mutant Dog / God in charge of flipping a giant lever is one of the few sensible things Elijah's done so far.
When life gave you guys with super strength, you used them for the heavy lifting. Vault doors, rusty levers, really stuck jar lids. That was only logical, right?
When Alex starts to berate Cain for wandering off instead of staying put like he told her, she effectively stops him by simply asking whether he'd have listened if their positions were reversed. Alex "looked like he wanted to strangle her, but in a fond way", but doesn't push the issue anymore because yeah, he wouldn't.
