This is a creature/Fakemon I’ve had in mind for a very long time.
Boefly spin silk which they turn into ribbons and tie around their body for flight. The ribbons also keeps them warm. When the winters get extra harsh, they will attach themselves to other Pokemon. Boefli are the main prey for their nemesis, the Nibboth
After weaving enough silk and gathering wool, a Boefli will evolve into Skarfli. Their warm coats keep them insulated and protected against harsh weather. Skarfli are more powerful and stand a slightly better chance against their Nibboth and Scizoth adversaries.
Boefli evolves into Skarli at Level 21 when in a cold climate and holding Warm Wool.
Ability: Insulate: Increases resistance against continuous Fire or Ice damage.
Best Stats: Sp. Attack, Sp. Defense
Common Attacks (Boefli): Bug Bite, Wrap, Icy Wind, Tickle
Common Attacks (Skarfli): Whirlwind, Blizzard, Aerial Ace, Bug buzz, Mist
Special Attack: Silk Wrap: (Bug, 15 PP) Lowers Speed, Increases Defense and Sp. Defense. Can target partner Pokemon instead.