Dual Ball flips 2 coins, letting a player search the deck for a Basic Pokémon card for each heads result, up to two Pokémon in one play. Unleashed's wording clarified that the deck is only shuffled 'if you do' find a Pokémon, tightening the earlier wording that always called for a shuffle afterward regardless of whether anything was found.
The earliest catalogued Dual Ball is the 2004 Team Magma vs Team Aqua printing, with art credited to Big Mama Tagawa, who also illustrated the Delta Species and Crystal Guardians reprints. Takashi Yamaguchi illustrated the Unleashed printing that introduced the reworded conditional shuffle, along with the Call of Legends reprint in the HeartGold and SoulSilver era, completing the card's five-printing run.
The EX era prints of Dual Ball feature a full-frame view of the same artwork and omit an exclusion of Baby Pokémon cards that had appeared in the card's earlier text, a small but notable wording difference between printings. The Delta Species and Crystal Guardians reprints kept Big Mama Tagawa's original artwork unchanged, giving the card three consecutive EX era printings under a single illustrator before Takashi Yamaguchi's later art appeared. Dual Ball's five printings across two illustrators, Big Mama Tagawa and Takashi Yamaguchi, give the card a clean split between its EX era and HeartGold and SoulSilver era art.
Team Magma vs Team Aqua printing is the earliest catalogued Dual Ball, illustrated by Big Mama Tagawa
Unleashed printing introduces the reworded conditional shuffle
Call of Legends printing carries the card into the HeartGold and SoulSilver era
It clarified the deck only shuffles 'if you do' find a Basic Pokémon, rather than always shuffling afterward.
Big Mama Tagawa illustrated the Team Magma vs Team Aqua, Delta Species, and Crystal Guardians printings.
An exclusion of Baby Pokémon cards from the search, present in earlier text, was omitted.
From Team Magma vs Team Aqua (2004) · 2 printings
Flip 2 coins. For each heads, search your deck for a Basic Pokémon card, show it to your opponent, and put it into your hand. Shuffle your deck afterward.
From Delta Species (2005) · 1 printing
Flip 2 coins. For each head, search your deck for a Basic Pokémon card, show it to your opponent, and put it into your hand. Shuffle your deck afterward.
From Unleashed (2010) · 2 printings
Flip 2 coins. For each heads, search your deck for a Basic Pokémon, show it to your opponent, and put it into your hand. If you do, shuffle your deck afterward.

Dual Ball
Item
First printed in Team Magma vs Team Aqua (2004)
Flip 2 coins. For each heads, search your deck for a Basic Pokémon, show it to your opponent, and put it into your hand. If you do, shuffle your deck afterward.