• English / United States: Ash's Krokorok
• Japanese / Japan: サトシのワルビル
• Japanese (Romanized) / Japan: Satoshi no Waruvile
• Japanese (Trans) / Japan: Satoshi's Waruvile

Ash's Krokorok was Pikachu rival. Ash's Krokorok evolved from Sunglasses Sandile during a battle against Pikachu at the end of BW20 after they had dealt with the troublesome Ducklett's. Pikachu's Electro Ball collided with Krokorok's Stone Edge which created a large blast that sent Krokorok flying into the air and they were unable to finish the battle. Krokorok wanted to continue its rivalry with Pikachu and after it recovered from the blast that sent it flying it began its search for Pikachu. It continued to be a wild Pokémon for a significant amount of time.

When Krokorok finally met up with Ash Ketchum and Pikachu again while they were on route for Fukiyose City, Krokorok explained to them that it had been following them during their travels and it tried to meet up with them at Raimon City and the Electric Stone Cave but it always got there a bit too late and they had moved on. It had also watched part of the final round of the Don George tournament where Pikachu was matched up against Iris' Excadrill. While in the Electric Stone Cave, Krokorok found Professor Cedric Juniper's fountain pen and tossed it away. The pen was later recovered by Professor Juniper who found it stuck in a Klinklang gear.

Double Battle Against Sean's Father's Scolipede and Sean's Father's Seismitoad

Glenn wanted to have a double battle with Mick and Pikachu, so Krokorok volunteered to battle on Pikachu's team. Glenn commanded both Sean's Father's Scolipede and Sean's Father's Seismitoad in a double battle against Pikachu and Ash's Krokorok.

Sean attempted to help out by giving Glenn advice by specifically telling him to match up Sean's Father's Seismitoad against Pikachu because of the type advantage but Glenn wouldn't take the advice. The inexperience of Glenn and his unwillingness to accept advice proved to be the reasons that Sean's Father's Scolipede and Sean's Father's Seismitoad lost the battle. Pikachu and Krokorok proved to be strong opponents and they easily won the match regardless.

Rival Battle vs Pikachu

After the double battle between Sean's Father's Scolipede and Sean's Father's Seismitoad was completed, Krokorok challenged Pikachu to finish their match that they started earlier in the day but was cut short as yet another Electro Ball/Stone Edge blast had sent them both flying in different directions. Ash Ketchum's strategy of aiming Thunderbolt at Krokorok's proved to be very effective as it created a hole in the ground that Krokorok tripped into leaving it vulnerable to Pikachu's Iron Tail which ended up knocking out Krokorok. The first fully completed battle between Pikachu and Krokorok had finally ended with Pikachu winning.

Demoralized by the loss, the Sunglasses Krokorok began to leave but Ash Ketchum invited it to join him on his journey with Pikachu and it happily agreed and was captured by Ash Ketchum.

Gym Battle against Skyla's Swoobat

In Skyla's air battle simulation, Skyla's Swoobat was matched up against Ash's Krokorok and because Ground type attacks wouldn't have any effect on her Swoobat, she gave it the victory. In the actual gym battle, Skyla's Swoobat and Ash's Krokorok were the first match-up and Ash's Krokorok wasn't able to hit Skyla's Swoobat at all. Cilan noted though that if Stone Edge hit completely, the taste of the battle might have changed. This was the first gym battle for Ash's Krokorok and it ended in a loss but everyone including Ash Ketchum seemed to think it did well despite the obvious type disadvantage.

Gym Battle against Brycen's Beartic

Brycen's Vanillish was the first Pokémon Brycen sent out and Ash Ketchum countered with his Krokorok. Astonish was an effective way to make Ash's Krokorok flinch, preventing it from attacking. When Ash's Krokorok broke free, it tried to dig into the ice but halfway down Brycen's Vanillish Blizzard froze the bottom part of Ash's Krokorok. Ash Ketchum knew he couldn't continue on like this and he recalled Krokorok.

After Ash Ketchum had knocked out Brycen's Vanillish and Brycen's Vanillish, Brycen's Beartic managed to knock out Ash's Pignite which left him with just his Ash's Krokorok who had already battled against Brycen's Vanillish. Seeing Brycen's Beartic made Ash's Krokorok want to become stronger itself and Ash's Krokorok was were waiting for this battle. It had a type advantage in the battle and together with Ash Ketchum, they battled with all their strength. Brycen's Beartic used Icicle Crash as a defense against Stone Edge. Ash Ketchum was able to counter that though by remembering Bianca's Emboar method that she used at the Donamite and Ash's Krokorok picked up a stray rock and jumped into the air to meet Brycen's Beartic for one final attack. The two of them collided in the air but Ash's Krokorok was the one that ended up victorious by defeating Brycen's Beartic.

Pokémon World Tournament Junior Cup

Ash's Krookodile evolved from Ash's Krokorok during a battle against Iris in the semi-finals round of the Pokémon World Tournament Junior Cup.