Physically Defensive Chesto-Rest Rotom (Wash)
Rotom-W @ Chesto Berry/Lum Berry
Bold Nature (+Def, -Att)
252 HP, 212 Def, 44 Speed
-Will 'O' Wisp
This set excels at checking dangerous physically inclined threats like Gale Wings Talonflame by coming in on a resisted hit and either Volt Switch while they get forced out or Will o Wisp to burn. Rest is to heal off status and fully restore health. Hydro Pump to smack Talonflame, Tyranitar and the like. Against Blaziken, this is an excellent way to bait Blaziken into using High Jump Kick, before switching into a ghost to make it lose half its health.
EVs may seem weird but let me explain. Max HP is obvious to be as tanky as possible, while I put 44EVs into Speed to outspeed Jolly Azumarill to get a Will 'O' Wisp/Volt Switch off before it hits me with Play Rough. Remaining EVs are thrown into Defense to be a fearsome check to many physical attackers.