It doesn't matter if they were creatures when they entered or who controlled them when they entered
The Rule of One Gold Star cards weren't just pretty facesthey came with a strict gameplay restriction printed right on the card: "You can't have more than 1 Pokmon in your deck." unlike the standard rule of four, or even the "one per species" rule for later mechanics
Sigh, here's your Serra Ascendant, Serra Avatar, Sphinx's Revelation, Absorb, yadda yadda, and some cards to spend life on and then either the life gain winning conditions like Felidar Sovereign or the auto-kill Black enchantments like Sanguine Bond and Exquisite Blood

Nami (OP03-040) OP03 Leader Alt Art (AA) Charlotte Katakuri (OP03-099) OP03 Leader Alt Art (AA) Portgas D Ace (OP03-001) OP03 Leader Alt Art (AA) Arlong (OP03-022) OP03 Leader Alt Art (AA) Charlotte Linlin (OP03-077) OP03 Leader Alt Art (AA) Rob Lucci (OP03-076) OP03 Leader Alt Art (AA) Kuro (OP03-021) OP03 Leader Alt Art (AA) Iceburg (OP03-058) OP03 Leader Alt Art (AA) Kalifa (OP03-081) OP03 Alternate Art (AA) Charlotte Linlin (OP03-114) OP03 Alternate Art (AA) Charlotte Pudding (OP03-112) OP03 Alternate Art (AA) Rob Lucci (OP03-092) OP03 Alternate Art (AA) Fire Fist (OP03-018) OP03 Alternate Art (AA) Marco (OP03-013) OP03 Alternate Art (AA) Charlotte Perospero (OP03-113) OP03 Alternate Art (AA) Charlotte Cracker (OP03-108) OP03 Alternate Art (AA) Spandam (OP03-086) OP03 Alternate Art (AA) Issho (OP03-078) OP03 Alternate Art (AA) Paulie (OP03-066) OP03 Alternate Art (AA) Zeff (OP03-047) OP03 Alternate Art (AA) Usopp (OP03-041) OP03 Alternate Art (AA) Krieg (OP03-025) OP03 Alternate Art (AA) Gin (OP03-024) OP03 Alternate Art (AA) Kaku (OP03-080) OP03 Alternate Art (AA) OP-02: Paramount War OP-02: Paramount War features a mix of alternate arts, collector cards, and popular One Piece characters

If you were lucky enough to pull one, check its market price at TCGplayer as virtually all of The Brothers War retro artifacts are worth at least $350 including Jalum Tome, Perilous Vault, and Altar of Dementia