Verdant Cavern (Japanese: 茂みの洞窟Verdant Cavern) is a location on Melemele Island in Alola, located in the northeastern portion of Route 2. It is the location of the trial of Ilima.
The trial begins as soon as the player enters Verdant Cavern; however, they can leave at any time, although this will reset the trial. Once the trial guide has stepped aside to grant access to the Totem's Den, the player can leave at any time without resetting the trial.
In this trial, the player must find and battle two YungoosSUS/Alolan RattataMUM and a GumshoosSUS/an Alolan RaticateMUM. Along the way, the player will face two Team Skull Grunts and battle one of them; once defeated, the two grunts will unwittingly help the player finish the trial. Despite not officially being part of the trial, the grunts act as if they are, resetting when the trial is reset.
In the battle with the Totem Pokémon, it will call its ally on its first turn; once the ally is defeated, the Totem Pokémon cannot call it again.
After defeating the Totem Pokémon, the player will be greeted by Ilima for completing the trial and will receive a Normalium Z as a reward. After completing the trial, wild Pokémon will appear in Verdant Cavern as both ambush encounters and cave tile encounters.
At first, Ash faced a Yungoos and Gumshoos, the Totem's ally Pokémon, which he defeated with the help of Pikachu and Rowlet. After this, Totem Gumshoos appeared, challenging Ash. It was able to defeat Rowlet, but was eventually taken down by Pikachu. As a reward for winning the battle, Totem Gumshoos gave Ash a Normalium Z and agreed to help in driving away the troublesome Rattata and Raticate. Unbeknownst to Ash and Hala, Tapu Koko secretly followed the trial as it took place.