After activating Vivien's last loyalty ability, the delayed triggered ability it creates will put a creature card onto the battlefield before the creature spell that caused the ability to trigger resolves
This card also takes an additional turn for the opponent to make up for, assuming they even have spare Energy cards on hand
Coronet, Rotom, Unidentified Fossil, Electric Memory, Looker, Yanmega, Pal Pad, Skuntank, Gardenia, Purugly, Floatzel, Missing Clover, Turtonator, Bronzong, Volkner, Cosmoem, Pokmon Fan Club, Gabite, Monferno, Fire Memory, Order Pad, Drifblim, Mars, Lopunny, Manaphy, Cynthia, Grotle, Escape Board, Alolan Dugtrio, Unit Energy LPM, Prinplup, Oranguru, Looker Whistle, Floatzel, Lillie, Magneton, Pal Pad, Luxio, Shieldon, Unidentified Fossil, Cherrim, Gumshoos, Ancient Crystal, Spiritomb, Rotom, Unit Energy GRW, Cosmoem, Looker, Yanmega, Purugly, Skuntank, Electric Memory, Turtonator, Mt
Don't worry, the vast majority of them are about design