[ORAS] What should I fill up my 6th slot with for Battle Spot Doubles?

[SjoerdDN]

Kangaskhan-Mega (F) @ Kangaskhanite
Ability: Parental Bond
EVs: 252 HP / 252 Atk / 4 Spe
Adamant Nature
- Fake Out
- Sucker Punch
- Power-Up Punch
-

Sylveon @ Choice Specs
Ability: Pixilate
EVs: 248 HP / 252 SpA / 8 SpD
Modest Nature
- Hyper Voice
- Psyshock
- Shadow Ball
- Protect

Amoonguss @ Black Sludge
Ability: Regenerator
EVs: 252 HP / 4 SpA / 252 SpD
Calm Nature
- Giga Drain
- Double Team
- Spore
- Rage Powder

Rotom-Wash @ Leftovers
Ability: Levitate
EVs: 248 HP / 8 SpA / 252 SpD
Calm Nature
- Hydro Pump
- Thunderbolt
- Thunder Wave
- Substitute

Greninja @ Life Orb
Ability: Protean
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Ice Beam
- Dark Pulse
- Scald
- Mat Block

This is the team so far.