Lol, no Marowak fans here? xD
Just kidding. Marowak can have a huge amount of Attack, but only if he has his Thick Club. I remember in Emerald (I cheated to catch a level 3 Cubone at the beginning, then cheated to get the Thick Club) beating just about anything I came across, although I never EV trained him or got him to level 100.
But if you can't manage to find a Thick Club, go with Original's idea and get a Cranidos (and later, a Rampardos). I have a spare Skull Fossil too, I think.
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(Work In Progress)</center>