Just think of the standard sets.. XD Natures are not required, but helpful.
Bronzor: Sassy/Relaxed, good HP/Defenses, poor Speed
Misdreavus: Timid/Modest, good SpAtk and Speed
Aron: Adamant, good HP/Atk
Dratini: Rash/Mild/Adamant, good Atk/Speed, decent Sp Atk if special based
Bronzor: Sassy/Relaxed, good HP/Defenses, poor Speed
Misdreavus: Timid/Modest, good SpAtk and Speed
Aron: Adamant, good HP/Atk
Dratini: Rash/Mild/Adamant, good Atk/Speed, decent Sp Atk if special based