I say AGGRON because it is a steel type and steel have the least weakness.
aggron
Aggron is a steel type Pokemon
You can't catch aggron but you can catch a lairon at victory road to get aggron train Lairon to level 42.
Aggron is number 306 in the pokedex.
You have to migrate a lairon or Aggron from ruby once you have lairon you must get it to level 42 then it evolves same with Aggron.
Aggron is a Rock and Steel type pokemon.
gyarados
Aggron can learn earthquake by using the TM on it.
that depends on your personal preference i personally think tyranitar over aggron
AGGRON! Rampardos's Attack is higher but his defenses are absolutely horrible.
Aggron is #306 in the national pokedex, and it is a Steel-Rock type Pokemon.