Wherever Slaking live, rings of over a yard in diameter appear in grassy fields. They are made by the Pokémon as it eats all the grass within reach while lying prone on the ground. It is the world’s most slothful Pokémon. However, it can exert horrifying power by releasing pent-up energy all at once. The world’s laziest Pokémon. It moves to another spot when there’s no food left within its reach.
Pokédex entry #289
Slaking in Pokémon GO
It's possible to hatch Slaking from an egg?
No, Slaking can't be hatched.
Which are Slaking’s strengths and weaknesses?
Slaking is a normal type Pokémon. normal type pokémons but weak against rock pokémons. They are not affected by ghost type pokémons.