[Rashaden]

I am working with my Nidoking that I hatched myself and am trying to find a moveset that will allow him to be able to stand his ground against other Pokemon that are his weakness. If you don't know, his weaknesses are:

Water / Ice / Ground / Psychic

This is how he looks currently:

Lv. 59

Ability - Poison Point

Stats:
HP - 185
Attack - 130
Defense - 117
Sp. Atk - 120
Sp. Def - 99
Speed - 141

Moveset:
Head Smash <-- Bred into him
Megahorn <-- to combat Psychic-types
Earthquake
Toxic

I don't know too much about IV's or EV's but I am getting the basics down for EV training I just don't really worry about it much at all. Advice would be appreciated. I was thinking of teaching him Thunderbolt but I'm not too sure...