Chatler first appeared in the Next Generation Comedy Grand Prix along with his Trainer, Pearl. During the skit, Pearl has Chatler blow the grass away. However, when Chatler did so, it revealed Diamond and Lax's lazy selves, which made both Pearl and Chatler mad. Chatler battled a pack of Starly with the help of Lax, Chimler, and Tru. They quickly defeat the Starly. Chatler was sent by Pearl to spy on Platinum as he wanted to know more about her.
Chatler assists Chimler in a battle against Luxio and its pack. However, Luxio stopped them from attacking and Pearl realized what was going on, so Pearl stopped the battle. Chatler arrived in Floaroma Town with the group and when Platinum went inside the Pick a Peck of Flowers Shop, Pearl had Chatler tell her to stay inside the flower shop so that she would not find out about Diamond's and Pearl's act as comedians when they were cheering up the Valley Windworks Manager's Daughter.
Later, Platinum dressed Chatler in a costume for the Super Contest. While the other Pokémon were dancing and bumped into each other while practicing, Chatler and Lax were on the side. Platinum borrowed Chatler for her battles in the Veilstone Gym. He went up against a Black Belt's Machoke and began with Aerial Ace. The outcome between the two wasn't shown. During the Gym Battle against Maylene, Chatler replaced Chimler when Chimler struggled against Riolu's Drain Punch. He went up against Meditite as Riolu was switched out because of its body emanating. Chatler was given a hard time in the battle since Meditite was very quick. Despite struggling, Chatler was able to defeat Meditite with Mirror Move. Afterwards, he was easily defeated by Riolu's Vacuum Wave.
Chatler fought alongside Diamond, Pearl, Paka and Uji's Pokémon against Team Galactic and their Staravia and Skuntank. He was able to finish the Staravia off by carrying Uji's Burmy and Burmy using Hidden Power at close range. He goes to the Great Marsh with the trio where he and Lax watched them try to capture some Pokémon there. While his Trainer was stuck along with Diamond and Platinum, a Carnivine appeared from the bushes and snatched Chatler and Lax. Carnivine placed them inside its mouth but Lax's body prevented Carnivine from swallowing them and they escaped.
In Celestic Town's ruins, Chatler fought Cyrus after Cyrus had Magnezone use its magnetic powers to draw out the camera hidden inside Lax's fur. Chatler quickly flew by and grabbed the camera but was subdued by Probopass's Gravity maneuver. Chatler's Trainer, unable to do a thing in said state, asks for Cyrus to lift the attack. This allowed for Chatler to gain his mobility and crush the camera Cyrus used to capture the images of the ruin paintings.
During Platinum's Gym battle against Fantina, Chatler goes on seesaw with Pearl to make Platinum realize that it is not best to fight the illusion.
Later, when Pearl decided to climb down the forest side, Chatler sensed two Wingull attacking. Chatler battled them and even though he had the speed advantage against them, Wingull's Roost gave Chatler problems. This required Chimler to join in with Chatler. They battled with the Wingull until Pearl noticed an injured one on its nest.
During Pearl's time at Fuego Ironworks, a group of Magby attack and Chatler along with Chimler take them on while he rode on Rayler to find Mr. Fuego. Arriving at Eterna City, Pearl gets spotted by two Clefairy, and Chatler and Rayler took them on. They were not able to score a critical hit on the Clefairy who used Lucky Chant to shield themselves from Chatler and Rayler scoring critical hits on them.
When Crasher Wake suggested to Pearl that he should catch his own Floatzel, he sent out Chatler to battle one of them. Chatler then saw Pearl behind a Croagunk billboard where his face substituted Croagunk's which made Chatler laugh as Crasher Wake suggested Pearl to have a good laugh. He trained rigorously with Pearl and got tired as they had one night to train.
Chatler arrived in the Galactic Veilstone Building where he told to Pearl that it was heavily guarded by Team Galactic and their Pokémon. When they went inside with the help of a swarm of Unown, Pearl separated with Chatler in order to find Diamond and had Chatler return the Poké Balls containing Torterra and Lickilicky to him. Chatler finds Diamond in the room containing the Lake guardians and Diamond was excited to see Chatler again. Diamond has Chatler mess the Advanced level Grunt with Chatter while Chingling was using Uproar at the same time so that the grunt would not hear the Pokédex communication between Diamond and Platinum. The noise battle between Chatler and Chingling created ultrasonic waves. The waves got weaker when they got tired.
Later, Pearl sent out Chatler and his whole team to take on Dialga and Palkia in order to save Sinnoh.
Later, Chatler gets attacked by Rotom as Rotom enjoyed playing jokes on him, Diamond and Pearl. Pearl flew on Chatler to find out where Giratina will strike next from using Shadow Force. Even though Charon planned on having Giratina attack Pearl and Chatler, Diamond pushed Pearl and Chatler out of the way to prevent them from getting hurt. After Diamond was sent to the Distortion World by Giratina, Chatler and his teammates avenged him by battling Giratina even though Pearl thought that they will lose but didn't care.
Chatler raced to Charon when Charon attempted to seal the portal of the Distortion World in order to take the machine Charon was using. However, the backfired when Charon adjusted part of the machine to have Chatler slam into Pearl. Chatler, along with Lax and Platinum's Rapidash, Charon controlled their movements with a remote but a Proteam Omega toy which Rotom possessed slapped the remote out of Charon's hands, restoring Chatler, Lax, and Platinum's Rapidash to normal. With Charon finally defeated, Chatler, Lax, Diamond, and Pearl return to performing their comedy show.