From the Azurilland Wiki, a database for the Pokémon series that anyone can contribute to
Grubbin (Japanese: アゴジムシ Agojimushi) is a Bug-type Pokémon introduced in the Generation VII games Pokémon Sun and Moon. It evolves into Charjabug at level 20.
→ Level 20 → → Level in Vast Poni Canyon →
| Generations I - VI
|Grubbin did not appear during the Generation I - VI games.
|Its strong jaw enables it to scrape trees and slurp out the sap. It normally lives underground.
|They often gather near places frequented by electric Pokémon in order to avoid being attacked by bird Pokémon.
Grubbin is likely based off of a larval beetle (a grub).
Grubbin's name appears to be based off the words grub and grubbing (to dig).