A Monotype Pokemon is a type of challenge run in the Pokemon games where the player can only use Pokemon that share a common type. This means that all the Pokemon on the players team must belong to the same type, whether it is Water, Bug, Dark, or Dragon. Both single- and dual-type Pokemon are allowed. The Monotype challenge is a great way to form a team around your favorite type(s) and not have to worry much about picking your favorites. However, the challenge lies in the teams weaknesses, as the player has to look out for moves or Pokemon that may defeat them.
The Monotype challenge is a self-imposed challenge where players limit themselves to one type, similar to a Gym Leader. The challenge is a great way to develop a playstyle in Pokemon. The best Pokemon games for a Monotype Run are Pokemon Sword and Shield, followed by Generation 6 and 7.