FireBug
Fire and Bug types: weaknesses, resistances and Pokémon
Fire and Bug Pokémon take quadruple damage from Rock moves, take double damage from Water and Flying moves and resist Grass, Ice, Fighting, Bug, Steel and Fairy moves.
The balance is even: 3 weaknesses and 6 resistances or immunities.
Fire moves are super effective against Grass, Ice, Bug and Steel and not very effective against Fire, Water, Rock and Dragon. Bug moves are super effective against Grass, Psychic and Dark and not very effective against Fire, Fighting, Poison, Flying, Ghost, Steel and Fairy.
To beat these Pokémon, your best pick is Rock moves. Avoid Grass, Ice, Fighting and Bug moves, which deal little or no damage.
There are 4 Pokémon with this combination, such as Larvesta, Volcarona, Sizzlipede and Centiskorch.