ITT: We come up with new challenge runs. Here's mine.

Bros and Hoes: it's similar to a wedlocke. Select any first pokemon (that has a gender), your second pokemon has to be of the same gender and at least one of the same typings as your first pokemon. For example a male Machamp and a male Conkeldurr is a pairing. In battle, these two pokemon can only switch out with each other. So Machamp and Conkeldurr can't switch with any other pokemon in your party, only each other. Use the same rules for the two other pairs in your party.

Example of full team:
Machamp & Conkeldurr (both male & fighting)
Delphox & Gothitelle (both female & psychic)
Swampert & Golisopod (both male & water)