My personal favorite OU team that revolves around Mega Lopunny (my motherfucking spirit pokémon okay) and others that support it! I use a Florges in place of Jirachi in my actual OR game as opposed to Showdown, so I'll be posting her set as well. The team treats me relatively well given my lack of experience and prediction skills, but I just felt like hearing others' opinions on it.
Mary (Garchomp) (F) @ Rocky Helmet
Ability: Rough Skin
EVs: 240 HP / 176 Def / 92 Spe
Impish Nature
- Stealth Rock
- Earthquake
- Dragon Tail
- Toxic
Talos (Talonflame) (M) @ Sharp Beak
Ability: Gale Wings
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Brave Bird
- Flare Blitz
- Swords Dance
- Roost
Winter (Weavile) (F) @ Life Orb
Ability: Pressure
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Knock Off
- Icicle Crash
- Ice Shard
- Poison Jab
Dolly (Jirachi) @ Leftovers
Ability: Serene Grace
EVs: 252 HP / 224 SpD / 32 Spe
Careful Nature
- Iron Head
- Thunder Wave
- Wish
- Protect
Koshosho (Florges) (F) @ Leftovers
Ability: Flower Veil
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
- Wish
- Synthesis
- Moonblast
- Aromatherapy
Eddie (Gengar) (M) @ Black Sludge
Ability: Levitate
EVs: 8 HP / 248 SpA / 252 Spe
Timid Nature
IVs: 0 Atk
- Hex
- Taunt
- Will-O-Wisp
- Sludge Wave (Bomb in OR)
Tammy (Lopunny-Mega) (F) @ Lopunnite
Ability: Limber
Shiny: Yes
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- High Jump Kick
- Return
- Fake Out
- Power-Up Punch
Mary (Garchomp) (F) @ Rocky Helmet
Ability: Rough Skin
EVs: 240 HP / 176 Def / 92 Spe
Impish Nature
- Stealth Rock
- Earthquake
- Dragon Tail
- Toxic
Talos (Talonflame) (M) @ Sharp Beak
Ability: Gale Wings
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Brave Bird
- Flare Blitz
- Swords Dance
- Roost
Winter (Weavile) (F) @ Life Orb
Ability: Pressure
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Knock Off
- Icicle Crash
- Ice Shard
- Poison Jab
Dolly (Jirachi) @ Leftovers
Ability: Serene Grace
EVs: 252 HP / 224 SpD / 32 Spe
Careful Nature
- Iron Head
- Thunder Wave
- Wish
- Protect
Koshosho (Florges) (F) @ Leftovers
Ability: Flower Veil
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
- Wish
- Synthesis
- Moonblast
- Aromatherapy
Eddie (Gengar) (M) @ Black Sludge
Ability: Levitate
EVs: 8 HP / 248 SpA / 252 Spe
Timid Nature
IVs: 0 Atk
- Hex
- Taunt
- Will-O-Wisp
- Sludge Wave (Bomb in OR)
Tammy (Lopunny-Mega) (F) @ Lopunnite
Ability: Limber
Shiny: Yes
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- High Jump Kick
- Return
- Fake Out
- Power-Up Punch