The thick, grass-like armor on a Chespin's head and back does not only protect them falling trees, vehicles, and large, charging pokemon who often fail to notice these much smaller pokemon; it also makes them a unique challenge to fight against. Attacking a Chespin from behind is a wasted effort for even powerful monsters, and although Chespin's speed is low even by the standards of unevolved pokemon, they need only turn in time to shrug off many enemy techniques. Super-effective attacks can break the shield, which is made of wood, and reaching a position directly above leaves Chespin with nowhere to turn for self-defense, so they have a special difficulty even by grass pokemon standards against birds.
Despite their extreme weakness to Fletchling and other birds of Kalos, Chespin are extremely popular among beginning trainers, who admire it for its armor and resilience as much as its cute appearance. These trainers are too new to rely on powerful teammates for support, so they teach a variety of tactics to their Chespin to compensate. Among the most popular such techniques are using the grass of standard outdoor battlefields to disguise their position and execute sneak attacks, or dipping their quills in poison before the match to hurl at avian foes. This developed ingenuity serves trainers well in their later careers, whether or not they continue using Chespin, but the need for human assistance speaks to the weakness which drove Chespin's extirpation from most of Kalos.
Chespin today are found only in remote Kiloude city, for in the rest of Kalos roads have replaced the open grasslands in which they hid from birds. The smaller patches of tall grass or flowers along many routes, although home to many pokemon, leave Chespin unable to escape or effectively disguise themselves.
