Speaking of Mega Pokemon, Banette gets Trick Room. Mega Banette has Prankster...so...Trick Room Banette anyone?
Banette @ Banettite
Ability: Insomnia (Prankster)
Nature: Relaxed
EVs: 252 HP, 252 Defense, 4 Attack | IVs: 0 Spe
- Trick Room
- Will-O-Wisp/Toxic/Taunt
- Return/Taunt
- Shadow Claw/Knock Off
Given that there are many other Pokemon to set up Trick Room around and there are other Mega Evolutions that can benefit from Trick Room, it might be hard to give up the Mega slot to Banette, but it does have its own advantages. Once you bring it in safely and get it Mega Evolved, preferably against an immunity or a sleep move (The defense investment still doesn't take Banette very far until the Mega stat boost), the +1 Priority support moves are immensely useful. Trick room would only be upgraded to -6 (I guess it'll go faster than opponent's Trick Room?), but Banette has access to Will-O-Wisp, Toxic, and Taunt also. What ones you choose (other than the obvious Trick Room) depend on what kind of support you want the rest of your team. Will-O-Wisp goes great with Mega Banette's decent defense stat, but you could also use Toxic as an alternative status inducing move. Taunt is an amazing move to have Prankster Priority on, so it should also be considered, as it could be used against opposing set-up sweepers attempting to take advantage of your set-up time and/or taunters trying to ruin your own Trick Room fun.
You could put in Taunt instead of Return if you don't care to have that second attacking move. Even with a Mega Evolution that boosts its Attack stat, Banette's physical movepool is so sad that it hurts, but the potential as a Trick Room supporter is uncanny. Nonetheless, that base 165 Attack (coming out to about 403 with just one EV of investment at level 100) is nothing to sniff at. As such, Shadow Claw will at least take advantage of that and give Banette a way to hit fast and hard under a Trick Room. Alternatively, in the spirit of support, Knock Off could be used to remove the opponent's items. The boost to 65 BP is a welcome upgrade to Knock Off.
I don't take total credit for this moveset. A friend of mine gave me the idea for Trick Room Mega Banette and I ran with it. I may try it out if I ever give a Trick Room team a shot.