So one threat I've been using that I haven't seen much discussion on is Murkrow. With the offensive and (implicit) defensive buffs to dark-types in XY (Steel no longer resists dark and ghost, which makes dark more valuable defensively for having those resistances), Murkow is very good now. One thing is that it's so damn versatile: Prankster Thunder Wave, Roost, Haze, Perish Song, Taunt, Tailwind, etc. make a defensive set extremely effective, while Brave Bird and Sucker Punch would make an offensive defogger set quite formidable (although it has to forgo Prankster for this). But here's my favorite set:
Murkrow @ Eviolite
Ability: Prankster
EVs: 248 HP / 252 Def / 8 SDef
Bold Nature
- Substitute / Taunt
- Roost
- Calm Mind
- Dark Pulse
Despite how its stats look, Murkrow is a bulky fucker when fully invested, because it has no need to invest in speed. For instance, it initially seems like the Knock Off buff would hurt it, but I would argue that the Knock Off buff actually helps Murkrow, because if Murkrow carries Substitute, Knock Off will not break the sub, which provides it with many opportunities for setup. So it's very easy to get a few Calm Minds in, and after about 2, special attackers won't be able to break your subs either. Basically, sorta like SubBU Braviary from last gen's NU, Murkrow can set up on a whole bunch of defensive shit.
0 Atk Lickilicky Body Slam vs. 248 HP / 252+ Def Eviolite Murkrow: 63-75 (19.5 - 23.2%) -- possible 5HKO (Knock Off does about 8%)
Edit: oh yeah prankster Featherdance is cool. Also, Kacaw.