The Fightinium Z (Japanese: カクトウZFighting Z) is a type of Z-Crystal introduced in Pokémon Sun and Moon. It is the type-specific Z-Crystal associated with the Fighting type and allows Pokémon to upgrade their Fighting-type moves to Z-Moves.
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.
In Trial and Tribulation!, Hala used a Fightinium Z with his Hariyama in his grand trial challenge with Ash. Later in the episode, Tapu Koko swapped out the Fightinium Z Ash was supposed to receive, as a reward for completing his Melemele grand trial, with an Electrium Z.
A full set of replicas of the type-specific Z-Crystals, including the Fightinium Z, appeared in A Team-on-Team Tussle!, where they were shown to Ash and his classmates by Professor Kukui. A full set of type-specific Z-Crystals, including the Fightium Z appeared in SM109, among the Z-Crystals that Hapu offered to Ash for having completed her grand trial.