It is not known to evolve into or from any other Pokémon.
Shuckle bears resemblance to a small turtle. Shuckle is encased in a very hard red shell that has many holes in it. Its body inside the shell is yellow and presumably very soft. Shuckle's limbs appear limp until in use and are completely able.
Shuckle are well-known for having high defenses, surpassing all other Pokémon in both physical and Special Defense. However, Shuckle's other stats are incredibly low, being either lowest or very near to lowest of all Pokémon.
Rather than actively hunting and foraging for food like most other Pokémon, it tends to collect berries and store them in its shell. The berries inside are liquefied and fermented by the Shuckle's digestive juices, which are then consumed by the Shuckle. These juices are also used to dissolve rocks for the Shuckle to hide under.
Shuckle tend to hide under rocks and fallen logs for long periods of time.
This Pokémon's main diet consists of berries, which it collects and stores in its shell.
This Pokémon was unavailable prior to Generation I.