Krookodile was used by Nanu to battle against Ash, to test whether the latter was worthy to take on the Grand Trial. Lycanroc used Tackle, but Krookodile blocked the attack, considering it lowered Lycanroc's power with the Intimidate ability. With Lycanroc angry, Krookodile crushed its Rock Throw with its tail and slapped it away. To stop Lycanroc's Bite, Krookodile used a combination of Sand Tomb and Mud-Slap on Lycanroc. After Lycanroc got enraged, it tried to use Bite on Krookodile's arm, who shook it off. Finally, it used Counter and Crunch on Lycanroc to defeat it.
Krookodile was used by Nanu as his first Pokémon in the Grand Trial against Ash and his Lycanroc. Like the previous time, Krookodile lowered Lycanroc's power with Intimidate. It used Mud-Slap on Lycanroc, who dodged that attack. However, Lycanroc fell in a Sand Tomb trap and got hit by Mud-Slap. Lycanroc became enraged for a moment, but it calmed down and exited the trap. Lycanroc fired Rock Throw, but Krookodile slammed the rocks to block the attack. Lycanroc repeated its attack, but so did Krookodile. Nanu noted Ash didn't want Lycanroc to have a close combat with Krookodile, who could use Counter to reflect the damage. Krookodile attempted to use Crunch, but missed, though it blocked Lycanroc's Rock Throw. Nanu thought Lycanroc was gutless to avoid using Accelerock or Bite against Krookodile's Counter. Ash, seeing Lycanroc's determination, had it use Accelerock. Krookodile went to use Counter, but Lycanroc was too fast for it and got hit by the attack. Due to that speed, Krookodile failed to block Rock Throw and was defeated.