Unaffected by item negating effects (such as Embargo and Klutz). Item manipulating effects (such as Trick and Fling) cannot remove a Z-Crystal from a Pokémon.
It reappeared in A Battle Hand-Off!, where Ash used it to perform 10,000,000 Volt Thunderbolt once again to defeat Jessie's Mimikyu at the Thrifty Megamart. Afterwards, it once again reverted back to an Electrium Z.
Ash's Electrium Z transformed into Pikashunium Z once more in From Z to Shining Z!, appearing in response to Professor Kukui performing Guardian of Alola with Tapu Koko. With their signature Z-Move, Ash and Pikachu were able to overpower Tapu Koko's Z-Move and defeat it. This time, however, the Pikashunium Z did not revert back into an Electrium Z afterwards.
In Ultra Exciting from the Shocking Start!, Ash was shown to have retrieved his Z-Power Ring and Pikashunium Z in preparation for his World Coronation Series match against Volkner. At the end of the match, Ash used them to perform 10,000,000 Volt Thunderbolt against Volkner's Electivire, overloading its Motor Drive and defeating it. The Pikashunium Z also saw usage in some of Ash's subsequent World Coronation Series battles.
Trivia
The name of the Pikashunium Z is a portmanteau of the words Pikachu and Ash (or Satoshi for Japan), referring to the fact that it can only be used by Pikachu in a cap, which is wearing Ash's hat.
The thunderbolt-like shape seen on the Pikashunium-Z resembles a Pikachu's tail. Additionally, the left edge of the "thunderbolt" resembles a Pikachu's fingers.
Bag item
Held item
