| Pokedex Entries: |
| Red | Its hard shell repels any kind of attack. It is vulnerable only when its shell is open. |
| Blue |
| Yellow | The shell can withstand any attack. However, when it is open, the tender body is exposed. |
| Gold | It swims facing backward by opening and closing its two-piece shell. It is surprisingly fast. |
| Silver | Grains of sand trapped in its shell mix with its body fluids to from beautiful pearls. |
| Crystal | Clamping on to an opponent reveals its vulnerable parts, so it uses this move only as a last resort. |
| Ruby | At night, this POKéMON uses its broad tongue to burrow a hole in the seafloor sand and then sleep in it. While it is sleeping, SHELLDER closes its shell, but leaves its tongue hanging out. |
| Sapphire |
| Emerald | At night, it burrows a hole in the seafloor with its broad tongue to make a place to sleep. While asleep, it closes its shell, but leaves its tongue hanging out. |
| FireRed | It is encased in a shell that is harder than diamond. Inside, however, it is surprisingly tender. |
| LeafGreen | Its hard shell repels any kind of attack. It is vulnerable only when its shell is open. |
| Diamond | It swims backward by opening and closing its two shells. Its large tongue is always kept hanging out. |
| Pearl |
| Platinum | It swims backward by opening and closing its two shells. Its large tongue is always kept hanging out. |
| Stadium 1 | Its shell is harder than diamond. It hides in sand on the sea floor and catches prey with its soft tongue. |
| Stadium 2 | It swims facing backward by opening and closing its two-piece shell. It is surprisingly fast. |
