These people who are saying Tyranitar is bad for being x4 weak to Fighting (by the way, before mega-evolving Aggron is x4 weak to Fighting too) are the same who say Garchomp or Landorus-T are bad for x4 weakness to Ice, Heatran is bad for being x4 weak to Ground and Gyarados bad for being x4 weak to Electric.
Let's just compare stats
>Tyranitar: pretty high stats in EVERYTHING. Only meh stat is Speed which it really doesn't need (and even counting it, it has freaking Dragon Dance). VERY HIGH attack, very good HP and Defense, very good Special Defense also which is boosted thanks to its ability.
>Aggron: only advantages over Tyranitar are its colosal 180 defense and Filter ability in Mega Aggron. Then: regular HP, very high attack which is still lower than Tyranitar, slower than Tyranitar, pathetic special defense stats
Except Defense and Fighting damage, Tyranitar is better than Aggron in everything.
