Vatolka is a special minion that appears instead of Arpatron in the capture training tutorial with Koris when a PocketStation is plugged in the PlayStation in Slot 1 as a Memory Card (see this video).
The element of the minion is determined by the unique ID provided by the PocketStation's serial number, with the determining digit resulting in: 0 being Fire elemental, 1 being Air elemental, 2 being Earth elemental, and 3 being Water elemental.
Despite the listed moves for Vatolka, it has been seen and captured with sometimes entirely different movesets and elements. It is also possible for Vatolka to have "illegal" move combinations, such as Fang - All Enemies.
Through the use of transferring saves between ePSXe and Xebra/Arbex, it is possible to have captured both Vatolka and Arpatron in the same save file. Furthermore, they count as having captured 2 different minions, despite them sharing the same in game capture flag.