I've been focusing on completing the national dex recently, so the levels vary. Here is some more specific information:
Gengar (Lv. 25)
Nature: Timid (Somewhat vain)
Ability: Levitate
Moves: Shadow Punch, Confuse Ray, Night Shade, Curse
Specialty: Attack
Weavile (Lv. 59)
Nature: Impish (Proud of its power)
Ability: Pressure
Moves: Slash, Beat Up, Metal Claw, Ice Shard
Specialty: Sp. Atk
Lucario (Lv. 100)
Nature: Lax (Mischievous)
Ability: Steadfast
Moves: ExtremeSpeed, Aura Sphere, Dragon Pulse, Heal Pulse
Specialty: Sp. Def
Flygon (Lv. 46)
Nature: Gentle (Highly persistent)
Ability: Levitate
Moves: Crunch, Dig, Faint Attack, Dragon Claw
Specialty: Defense
Magcargo (Lv. 38)
Nature: Modest (Likes to run)
Ability: Magma Armor
Moves: AncientPower, Flame Burst, Lava Plume, Rock Throw
Speciality: Attack
Xatu (Lv. 25)
Nature: Modest (Capable of taking hits)
Ability: Synchronize
Moves: Peck, Miracle Eye, Night Shade, Teleport
Specialty: Attack
Are these the Pokemon you plan on using for the League right?