Nineage
Pugnacious.
Hasn't been updated in a while but I wanted to add two cores I've been using:
I think FWG cores tend to be a fun way to start balance teams, and I've built a few that I like with this one. Basically, Mareanie is a cool new Pokemon that can handle most of the metagame except Psychic- and Ground-types, both of which are conveniently taken care of by Pumpkaboo. Additionally, Mareanie can set up Toxic Spikes which Pumpkaboo keeps on the field by spinblocking. However, the duo share a Pawniard weakness, which brings in Ponyta, which can scare Knock Off users, burn Physical attackers, and handle stallbreakers like Snivy better than the other two. The core is overall a bit trapper weak (as balance cores are), but it can survive decently even if one of its members get trapped, and hopefully trapping won't be an issue in the metagame too much longer anyway. The set has some fun variations, like Z-Trick-or-Treat Pump, but I'll let you figure those out on your own.
I LOVE using Aipom. Unfortunately, it lost one of its most fun partners with the fall of Fletchling this generation, but in some ways, Doduo works even better. Basically, these two Pokemon both hit insanely hard, and they share basically the same list of checks and counters. Whatever can be switched in to stop one can be hit by Knock Off or donked by a STAB move, leaving the game open for the other to sweep. Good partners include Pokemon that handle priority, and hazard support to help wear down the opposing team more quickly.
Pumpkaboo-Small (Pumpkaboo-Super) @ Eviolite
Ability: Frisk
Level: 5
EVs: 204 HP / 196 Def / 4 SpA / 76 SpD / 28 Spe
Calm Nature
IVs: 0 Atk
- Giga Drain
- Will-O-Wisp
- Fire Blast
- Synthesis
Ponyta @ Eviolite
Ability: Run Away
Level: 5
EVs: 76 Atk / 156 Def / 76 SpD / 196 Spe
Jolly Nature
- Flare Blitz
- Morning Sun
- Will-O-Wisp
- Flame Charge / Wild Charge
Mareanie @ Eviolite
Ability: Regenerator
Level: 5
EVs: 196 HP / 100 Def / 12 SpA / 180 SpD
Modest Nature
IVs: 0 Atk
- Scald
- Toxic Spikes
- Sludge Bomb
- Recover
Ability: Frisk
Level: 5
EVs: 204 HP / 196 Def / 4 SpA / 76 SpD / 28 Spe
Calm Nature
IVs: 0 Atk
- Giga Drain
- Will-O-Wisp
- Fire Blast
- Synthesis
Ponyta @ Eviolite
Ability: Run Away
Level: 5
EVs: 76 Atk / 156 Def / 76 SpD / 196 Spe
Jolly Nature
- Flare Blitz
- Morning Sun
- Will-O-Wisp
- Flame Charge / Wild Charge
Mareanie @ Eviolite
Ability: Regenerator
Level: 5
EVs: 196 HP / 100 Def / 12 SpA / 180 SpD
Modest Nature
IVs: 0 Atk
- Scald
- Toxic Spikes
- Sludge Bomb
- Recover
Aipom @ Life Orb
Ability: Skill Link
Level: 5
EVs: 76 HP / 196 Atk / 236 Spe
Jolly Nature
- Fake Out
- Knock Off
- Fury Swipes
- Brick Break
Doduo @ Life Orb
Ability: Early Bird
Level: 5
EVs: 236 Atk / 240 Spe
Naive Nature
- Brave Bird
- Knock Off
- Quick Attack
- Jump Kick
OR
Doduo @ Choice Scarf
Ability: Early Bird
Level: 5
EVs: 236 Atk / 240 Spe
Adamant Nature
- Brave Bird
- Return
- Knock Off
- Quick Attack
Ability: Skill Link
Level: 5
EVs: 76 HP / 196 Atk / 236 Spe
Jolly Nature
- Fake Out
- Knock Off
- Fury Swipes
- Brick Break
Doduo @ Life Orb
Ability: Early Bird
Level: 5
EVs: 236 Atk / 240 Spe
Naive Nature
- Brave Bird
- Knock Off
- Quick Attack
- Jump Kick
OR
Doduo @ Choice Scarf
Ability: Early Bird
Level: 5
EVs: 236 Atk / 240 Spe
Adamant Nature
- Brave Bird
- Return
- Knock Off
- Quick Attack