Mega Kangaskhan, Gengar, Scizor
Kangaskhan @ Kangaskhanite
Ability: Scrappy -> Parental Bond
EVs: 252 Atk / 252 Spd / 4 HP
Nature: Adamant (+Atk, -SpA)
Power-Up Punch / Return / Earthquake / Sucker Punch
No explanation necessary, I'd imagine. Lead the fight, Mega Evolve, power up, wreck house. Scared of the usual suspects, so I figured I'd find her a partner that was nimble and gave no cares about Fighting moves.
Gengar @ Focus Sash (AKA what I spent my 48 BP on that I got winning normal Singles to unlock Super)
Ability: Levitate
EVs: 252 SpA / 252 Spd / 4 HP
Nature: Modest (+SpA, -Atk)
Shadow Ball / Dazzling Gleam / Thunderbolt / Destiny Bond
Destiny Bond works like a charm in the Maison, especially since opponents will take any chance they can get to secure a KO. The unusual moveset is due to having so few answers to Water, Flying and Dragon Pokemon in my party, as well as providing a super-effective option against the many Fighting-types I switch Gengar into. I figured I wanted something bulky in the third spot, to tank hits and generally deal with whatever was left. Given that I'd spent so little time collecting Pokemon, had no BP, and have limited options barring some Wonder Trade shenanigans, I approached my neighbors and had them trade to evolve another guy, just as they had with Gengar.
Scizor @ Leftovers
Ability: Technician
EVs: sorry, couldn't tell you because I had prepared this one a year ago, but based on the display in Super Training, I think it's the 248 HP / 252 Atk / 8 SpD spread in the Choice Band set in Scizor's analysis
Nature: Adamant (+Atk, -SpA)
Bullet Punch / Swords Dance / Aerial Ace / Brick Break
This is the one I'm least happy with, though Scizor's done what it needs to every single time it comes out. Bullet Punch and sometimes SD are the only moves I use anyway, though I did use Aerial Ace on Volcarona2, which would have ended my streak otherwise (Volcarona being both the only Bug and the only Fire-type I feel particularly worried about). I think my original intention from a year ago, before even thinking about the Maison, was to go CB Scizor (the EVs seem to bear that evidence out), though without ORAS, I'd have to round out my four moves on the cleaner here without Superpower. Still, for now, the strategy is generally to finish the match by picking off the remaining foes with Bullet Punch, or come in during Trick Room since it's the slowest thing I've got (in which case I'm probably better off taking Night Slash somewhere on the set to combat the Ghosts and Psychics that Trick Room tends to come from).