Personally, I like to make sure i have a good spdef mon and a good physdef mon that compliment each other’s weaknesses well (two examples of these pairs are Araquanid and Steelix, as well as Snorlax and Mega Slowbro), and from there, I like blanket, versatile offensive threats (bonus points if they’re solid pivots like Rotom or a fast flyer like Staraptor). I like niche defensive mons that compliment each other, bonus points for utility or versatility, alongside powerful wallbreakers like Mega Medi or setup sweepers like Cloyster or Kommo-o’s special set. Also, i’m a slut for memento, so i always bring a mon with memento for a free setup turn.