Mareep

“If static elec­ tricity builds in its body, its fleece doubles in volume. Touching it will shock you.”

— Pokémon Gold

“Its fleece grows continually. In the summer, the fleece is fully shed, but it grows back in a week.”

— Pokémon Silver

“It stores lots of air in its soft fur, allowing it to stay cool in summer and warm in winter.”

— Pokémon Crystal