While on route to Suzuran Island, Ash and friends meet Buck on the ship taking them to the Sinnoh League. Buck is a treasure hunter and he shows them a treasure map.
Ash and his friends ask to help Beck find the treasure. He agrees and the group begins searching for the treasure. After avoiding many Pokémon and obstacles on the way, they arrived at an ancient stone pyramid.
A Claydon appears and takes care of Team Rocket but Buck was determined to capture it. Using his Baltoy, he was able to weaken the Claydon and capture it. After capturing the Claydon, a box appears with many ancient artifacts which he was happy to find although Ash and friends were hoping for golden treasure.