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Yes Truant Durant seems to be released in Rugged Mountain. If the Subway trainers don´t start switiching with truant a full setup with every mon is nearly guaranted. Only first turn protect could fuck up that strategie.
If you use Gliscor you can use Suicune as a third member. It´s a beast on is own,covers Gliscors Ice and Water weakness and PP Stall can be handy.
Or if you want something less common use Sword Dance Empoleon :D
They should finally release the Snarl TM. I want to use my Evolith Prankster Murcrow but without Snarl it can´t cripple special attackers :/
Murcrow @ Evolith
Calm
252 HP, 252 SpDef, 4 Def
Featherdance
Snarl
Taunt/Roost
Thunderwave/Roost
It would be so awesome...
Edit: For Illumise: the...
I wonder if anybody hacked a Keldeo/Meloetta/Genesect and knows if they are usable in the Battle Subway. My theory is Keldeo can be used, the other two can´t. Is this correct?