If Donphan were to tackle with its hard body, even a house could be destroyed. Using its massive strength, the Pokémon helps clear rock and mud slides that block mountain trails. The longer and bigger its tusks, the higher its rank in its herd. The tusks take long to grow. It has sharp, hard tusks and a rugged hide. Its Tackle is strong enough to knock down a house.
Pokédex entry #232
Donphan in Pokémon GO
It's possible to hatch Donphan from an egg?
No, Donphan can't be hatched.
Which are Donphan’s strengths and weaknesses?
Donphan is a ground type Pokémon. ground type pokémons are strong against fire, electric, poison, rock, steel pokémons but weak against grass, bug pokémons. They are not affected by flying type pokémons.