Glastrier

Glastrier's immense Attack stat, backed up by a good STAB move and extremely useful coverage options, makes it capable of breaking through most foes. Its bulk is nothing to sneeze at either, and it can create extremely tanky Substitutes to protect itself from status and weaker hits from the likes of Vileplume and Vaporeon. Glastrier's two main problems are its poor defensive typing and very low Speed; these leave it vulnerable to the powerful STAB moves and coverage attacks of most other wallbreakers such as Passimian and Exploud, so its defensive utility is less than it appears on paper. Glastrier is also unable to make progress against certain answers such as Diamond Storm Diancie, Quagsire, and Arcanine without a lot of support. Worse yet, other stallbreakers like Salazzle and Growth Vileplume boast superior typings and Speed, so it is hard to justify Glastrier on teams given it offers little in comparison.