Keldeo @ Life Orb / Fightinium Z
Ability: Justified
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
IVs: 0 Atk
- Surf
- Focus Blast
- Ice Beam
- Nasty Plot
From: Weavile
Weavile gets Nasty Plot and a pretty good special movepool which fits Keldeo's needs quite well. It retains good STABs in Surf and Focus Blast, finally gets a good Ice move (or use Shadow Ball just cuz), and a way to boost SpA quickly in Nasty Plot. Overall pretty decent.
Lopunny-Mega @ Lopunnite
Ability: Cute Charm
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Return
- Close Combat
- Poison Jab / Aqua Tail / Aqua Jet
- Swords Dance
From: Keldeo
This is just Mega Lopunny, but replace Ice Punch and Fake Out for another coverage move and Swords Dance. Not bad. Also, no stupid HJK misses.
Chandelure @ Choice Scarf
Ability: Infiltrator / Flash Fire
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
IVs: 0 Atk
- Shadow Ball
- Ice Beam
- Thunderbolt
- Switcheroo
From: Lopunny
Chandy here unfortunately loses it's great Fire STAB (unless you really want to use HP Fire), but in return you keep your good STAB in Shadow Ball and get great BoltBeam coverage. You even get a Trick clone to cripple walls with.
Serperior @ Grassium Z / Life Orb
Ability: Contrary
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
IVs: 0 Atk
- Energy Ball
- Overheat
- Will-O-Wisp
- Hidden Power [Ice]
From: Chandelure
It's Overheat Serp. Do you really need an explanation?
Seismitoad @ Leftovers
Ability: Water Absorb
EVs: 252 HP / 252 Atk / 4 SpD
Adamant Nature
- Aqua Tail
- Knock Off / Substitute
- Coil
- Synthesis
From: Serperior
Seismitoad is literally only here to give Weavile moves but I guess it can some sort of stallbreaker?
Weavile @ Life Orb / Focus Sash
Ability: Pressure
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Knock Off
- Ice Punch
- Earthquake / Low Kick / Poison Jab
- Stealth Rock
From: Seismitoad
Weavile retains it's good STAB combination while gaining or retaining great Ground/Fighting/Poison/Rock coverage moves and also acts as a suicide Rocks lead.